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Starts at zero/basic English and samples progressively through C2. At the end you receive an estimated level.
The major English grammar structures not covered by the other learning modules, with rich examples, comparisons and randomized practice.
Cards are shuffled on each fresh page load. Use the controls to focus the lesson set.
A gerund is an -ing form functioning as a noun, for example as subject or object.
verb-ing as subject/objectpreposition + verb-ingDefining relatives identify which person or thing; non-defining relatives add extra information and are set off by commas.
noun + defining relativenoun, non-defining relative,In formal style, a preposition may come before whom or which. In less formal English the preposition often stays at the end of the relative clause.
the person to whom I spokethe company for which she worksEnglish clauses are built around a subject and a verb, with optional objects, complements and adverbials.
Subject + VerbSubject + Verb + ObjectSubject + Linking Verb + ComplementThird conditionals imagine a different past; mixed conditionals connect an unreal past with a present result or vice versa.
If + past perfect, would have + past participleIf + past perfect, would + base verbComplex sentences can express purpose, result and concession with structures such as so that, so/such...that, although and even though.
so that + clauseso + adjective + thatsuch + noun phrase + thatalthough/even though + clauseReported questions use statement word order and normally do not use do/does/did.
asked + wh-word + subject + verbasked + if/whether + subject + verbConditional meaning can be expressed with alternatives to if. Unless means if not; provided that and as long as express a necessary condition.
unless + affirmative clauseprovided/providing that + clauseas long as + clauseEnglish verbs select different complement types: gerund, to-infinitive, bare infinitive, object + infinitive, or that-clause. These patterns must often be learned with the verb.
avoid doingdecide to dolet someone dowant someone to doinsist that + clauseParticiple clauses compress information when the understood subject is the same as the subject of the main clause.
Walking home, ...Built in 1900, ...Having finished, ...In formal literary style, so + adjective or such + be can be fronted and followed by inversion for strong emphasis.
So + adjective + auxiliary + subject + that...Such + be + noun phrase + that...Having + past participle shows that one action was completed before the action in the main clause. The passive form is having been + past participle.
Having + past participle, main clauseHaving been + past participle, main clauseThe zero conditional describes general results; the first conditional describes a real future possibility.
If + present, presentIf + present, will + base verbHave/get + object + past participle means that someone arranges for another person to perform a service or action.
have + object + past participleget + object + past participleWith some verbs, gerund and infinitive are both possible but the meaning changes, such as remember, stop and try.
remember doing / remember to dostop doing / stop to dotry doing / try to doSome verbs take to + infinitive, while modal verbs and certain structures take a bare infinitive.
want to gocan golet/make + object + base verbCommands are commonly reported with tell/ask + object + infinitive; time and place words may change according to viewpoint.
told/asked + object + to-infinitivenow → then; today → that day; here → thereEnglish can emphasize a statement with do/does/did or focus information with it-clefts and what-clefts.
I do agree.It was X that...What I need is...Items joined in a list or comparison should normally have matching grammatical form.
to read, to write, and to speakreading, writing, and speakingThe second conditional expresses unreal, imaginary or unlikely present and future situations.
If + past simple, would + base verbObjects receive the action, while complements describe or identify the subject or object.
S + V + OS + linking V + subject complementS + V + O + object complementWish/if only + past perfect expresses regret about a past event that cannot be changed.
wish/if only + had + past participleAn independent clause can stand alone; a dependent clause needs another clause to complete the meaning.
Independent clauseSubordinator + dependent clauseAs if/as though can introduce comparisons that are real or unreal. A past form can signal an unreal present comparison, and past perfect can signal an unreal past comparison.
as if/as though + presentas if/as though + pastas if/as though + past perfectA complete sentence needs an independent clause. Two independent clauses need correct coordination or punctuation such as a period, semicolon, or comma plus coordinator.
independent clause. Independent clause.independent clause; independent clauseindependent clause, and/but/so independent clauseFormal conditionals can omit if and invert had, were or should with the subject.
Had I known, ...Were I you, ...Should you need help, ...Some relative clauses can be reduced to participle phrases when the meaning remains clear.
people who live here → people living hereproducts that were made locally → products made locallyPresent participles often describe an active or ongoing relation; past participles often describe a completed or passive relation.
verb-ingpast participle (V3)Writers and speakers can move an element to the front to establish a topic, contrast or emphasis, especially in literary and conversational styles.
Fronted adverbial + clauseObject/topic + clause/commentThe passive focuses on the receiver of an action. It is formed with be plus a past participle.
be + past participleObject of active sentence → subject of passiveEnglish relies strongly on word order. Frequency adverbs usually go before a lexical verb but after be.
Subject + adverb + lexical verbSubject + be + adverbVerb + object + manner/place/timeAfter certain verbs and adjectives, especially in formal American English, a that-clause may use the base verb for all subjects.
recommend that + subject + base verbit is essential that + subject + base verbFormal emphasis can place a negative or restrictive adverbial first and invert the auxiliary and subject.
Never have I...Rarely do they...Not only did she...The passive keeps the tense in the auxiliary be while the main verb stays in the past participle form.
is done / was done / has been done / will be done / is being doneEnglish often avoids repetition by omitting recoverable words or replacing them with forms such as one, do, so and neither.
I can swim and she can too.the red oneI think so.Different reporting verbs take different complements: infinitive, gerund, object + infinitive, or that-clause.
agree to dodeny doingadvise object to dosuggest that + clause / suggest doingReported speech retells what someone said, often with tense backshift when the reporting verb is in the past.
said (that) + clausetold + object + clauseWould rather can express preference; with a different subject it often takes a past form. It’s time can also take a past form for desired action now.
would rather + base verbwould rather + subject + pastit is time + subject + pastWords such as each, every, either and neither are normally singular when they are the grammatical head of the subject.
Each/Every + singular noun + singular verbEither/Neither + singular verbCollective nouns and expressions of amount can take singular or plural agreement depending on meaning and variety of English.
A team is... / The team are...Ten dollars is...Coordinators link equal units; subordinators make one clause dependent on another.
clause, and/but/so clausebecause/although/when + clauseA relative pronoun can sometimes be omitted when it is the object of a defining relative clause, but not when it is the subject.
the book (that) I boughtthe man who calledWhose expresses possession; where relates to places; when relates to times, though preposition + which is also possible in formal style.
person whose + nounplace where + clausetime when + clauseIn existential there structures, the verb commonly agrees with the following notional subject in formal standard English. In relative clauses, agreement depends on the antecedent represented by the relative pronoun.
There is + singularThere are + pluralone of the people who are...Wish + past form commonly expresses dissatisfaction with the present; wish + would can express a desired change in behavior or situation.
wish + past simplewish + would + base verbIn the present simple, third-person singular subjects normally take a verb ending in -s; plural subjects use the base form.
He/She/It + verb-sI/You/We/They + base verbFormal English often reports general beliefs or claims with impersonal passive structures or subject + passive reporting verb + infinitive.
It is said that + clauseSubject + is said/believed/thought + to-infinitiveA noun clause functions like a noun; an adverb clause adds information about time, reason, condition, contrast or purpose.
I know + that-clausewhat/why/how + clausesubordinator + adverb clauseCards are shuffled on each fresh page load. Use the controls to focus the lesson set.
English clauses are built around a subject and a verb, with optional objects, complements and adverbials.
Subject + VerbSubject + Verb + ObjectSubject + Linking Verb + ComplementObjects receive the action, while complements describe or identify the subject or object.
S + V + OS + linking V + subject complementS + V + O + object complementA complete sentence needs an independent clause. Two independent clauses need correct coordination or punctuation such as a period, semicolon, or comma plus coordinator.
independent clause. Independent clause.independent clause; independent clauseindependent clause, and/but/so independent clauseEnglish relies strongly on word order. Frequency adverbs usually go before a lexical verb but after be.
Subject + adverb + lexical verbSubject + be + adverbVerb + object + manner/place/timeCards are shuffled on each fresh page load. Use the controls to focus the lesson set.
Complex sentences can express purpose, result and concession with structures such as so that, so/such...that, although and even though.
so that + clauseso + adjective + thatsuch + noun phrase + thatalthough/even though + clauseAn independent clause can stand alone; a dependent clause needs another clause to complete the meaning.
Independent clauseSubordinator + dependent clauseCoordinators link equal units; subordinators make one clause dependent on another.
clause, and/but/so clausebecause/although/when + clauseA noun clause functions like a noun; an adverb clause adds information about time, reason, condition, contrast or purpose.
I know + that-clausewhat/why/how + clausesubordinator + adverb clauseCards are shuffled on each fresh page load. Use the controls to focus the lesson set.
Words such as each, every, either and neither are normally singular when they are the grammatical head of the subject.
Each/Every + singular noun + singular verbEither/Neither + singular verbCollective nouns and expressions of amount can take singular or plural agreement depending on meaning and variety of English.
A team is... / The team are...Ten dollars is...In existential there structures, the verb commonly agrees with the following notional subject in formal standard English. In relative clauses, agreement depends on the antecedent represented by the relative pronoun.
There is + singularThere are + pluralone of the people who are...In the present simple, third-person singular subjects normally take a verb ending in -s; plural subjects use the base form.
He/She/It + verb-sI/You/We/They + base verbCards are shuffled on each fresh page load. Use the controls to focus the lesson set.
Third conditionals imagine a different past; mixed conditionals connect an unreal past with a present result or vice versa.
If + past perfect, would have + past participleIf + past perfect, would + base verbConditional meaning can be expressed with alternatives to if. Unless means if not; provided that and as long as express a necessary condition.
unless + affirmative clauseprovided/providing that + clauseas long as + clauseThe zero conditional describes general results; the first conditional describes a real future possibility.
If + present, presentIf + present, will + base verbThe second conditional expresses unreal, imaginary or unlikely present and future situations.
If + past simple, would + base verbCards are shuffled on each fresh page load. Use the controls to focus the lesson set.
Have/get + object + past participle means that someone arranges for another person to perform a service or action.
have + object + past participleget + object + past participleThe passive focuses on the receiver of an action. It is formed with be plus a past participle.
be + past participleObject of active sentence → subject of passiveThe passive keeps the tense in the auxiliary be while the main verb stays in the past participle form.
is done / was done / has been done / will be done / is being doneFormal English often reports general beliefs or claims with impersonal passive structures or subject + passive reporting verb + infinitive.
It is said that + clauseSubject + is said/believed/thought + to-infinitiveCards are shuffled on each fresh page load. Use the controls to focus the lesson set.
Reported questions use statement word order and normally do not use do/does/did.
asked + wh-word + subject + verbasked + if/whether + subject + verbCommands are commonly reported with tell/ask + object + infinitive; time and place words may change according to viewpoint.
told/asked + object + to-infinitivenow → then; today → that day; here → thereDifferent reporting verbs take different complements: infinitive, gerund, object + infinitive, or that-clause.
agree to dodeny doingadvise object to dosuggest that + clause / suggest doingReported speech retells what someone said, often with tense backshift when the reporting verb is in the past.
said (that) + clausetold + object + clauseCards are shuffled on each fresh page load. Use the controls to focus the lesson set.
A gerund is an -ing form functioning as a noun, for example as subject or object.
verb-ing as subject/objectpreposition + verb-ingEnglish verbs select different complement types: gerund, to-infinitive, bare infinitive, object + infinitive, or that-clause. These patterns must often be learned with the verb.
avoid doingdecide to dolet someone dowant someone to doinsist that + clauseWith some verbs, gerund and infinitive are both possible but the meaning changes, such as remember, stop and try.
remember doing / remember to dostop doing / stop to dotry doing / try to doSome verbs take to + infinitive, while modal verbs and certain structures take a bare infinitive.
want to gocan golet/make + object + base verbCards are shuffled on each fresh page load. Use the controls to focus the lesson set.
Participle clauses compress information when the understood subject is the same as the subject of the main clause.
Walking home, ...Built in 1900, ...Having finished, ...Having + past participle shows that one action was completed before the action in the main clause. The passive form is having been + past participle.
Having + past participle, main clauseHaving been + past participle, main clauseSome relative clauses can be reduced to participle phrases when the meaning remains clear.
people who live here → people living hereproducts that were made locally → products made locallyPresent participles often describe an active or ongoing relation; past participles often describe a completed or passive relation.
verb-ingpast participle (V3)Cards are shuffled on each fresh page load. Use the controls to focus the lesson set.
Defining relatives identify which person or thing; non-defining relatives add extra information and are set off by commas.
noun + defining relativenoun, non-defining relative,In formal style, a preposition may come before whom or which. In less formal English the preposition often stays at the end of the relative clause.
the person to whom I spokethe company for which she worksA relative pronoun can sometimes be omitted when it is the object of a defining relative clause, but not when it is the subject.
the book (that) I boughtthe man who calledWhose expresses possession; where relates to places; when relates to times, though preposition + which is also possible in formal style.
person whose + nounplace where + clausetime when + clauseCards are shuffled on each fresh page load. Use the controls to focus the lesson set.
Wish/if only + past perfect expresses regret about a past event that cannot be changed.
wish/if only + had + past participleAs if/as though can introduce comparisons that are real or unreal. A past form can signal an unreal present comparison, and past perfect can signal an unreal past comparison.
as if/as though + presentas if/as though + pastas if/as though + past perfectWould rather can express preference; with a different subject it often takes a past form. It’s time can also take a past form for desired action now.
would rather + base verbwould rather + subject + pastit is time + subject + pastWish + past form commonly expresses dissatisfaction with the present; wish + would can express a desired change in behavior or situation.
wish + past simplewish + would + base verbCards are shuffled on each fresh page load. Use the controls to focus the lesson set.
In formal literary style, so + adjective or such + be can be fronted and followed by inversion for strong emphasis.
So + adjective + auxiliary + subject + that...Such + be + noun phrase + that...English can emphasize a statement with do/does/did or focus information with it-clefts and what-clefts.
I do agree.It was X that...What I need is...Formal conditionals can omit if and invert had, were or should with the subject.
Had I known, ...Were I you, ...Should you need help, ...Formal emphasis can place a negative or restrictive adverbial first and invert the auxiliary and subject.
Never have I...Rarely do they...Not only did she...Cards are shuffled on each fresh page load. Use the controls to focus the lesson set.
Items joined in a list or comparison should normally have matching grammatical form.
to read, to write, and to speakreading, writing, and speakingWriters and speakers can move an element to the front to establish a topic, contrast or emphasis, especially in literary and conversational styles.
Fronted adverbial + clauseObject/topic + clause/commentAfter certain verbs and adjectives, especially in formal American English, a that-clause may use the base verb for all subjects.
recommend that + subject + base verbit is essential that + subject + base verbEnglish often avoids repetition by omitting recoverable words or replacing them with forms such as one, do, so and neither.
I can swim and she can too.the red oneI think so.Side-by-side study cards for grammar distinctions learners commonly mix up.
Defining relatives identify which person or thing; non-defining relatives add extra information and are set off by commas.
noun + defining relativenoun, non-defining relative,Third conditionals imagine a different past; mixed conditionals connect an unreal past with a present result or vice versa.
If + past perfect, would have + past participleIf + past perfect, would + base verbReported questions use statement word order and normally do not use do/does/did.
asked + wh-word + subject + verbasked + if/whether + subject + verbWith some verbs, gerund and infinitive are both possible but the meaning changes, such as remember, stop and try.
remember doing / remember to dostop doing / stop to dotry doing / try to doWish/if only + past perfect expresses regret about a past event that cannot be changed.
wish/if only + had + past participleAn independent clause can stand alone; a dependent clause needs another clause to complete the meaning.
Independent clauseSubordinator + dependent clauseSome relative clauses can be reduced to participle phrases when the meaning remains clear.
people who live here → people living hereproducts that were made locally → products made locallyEnglish relies strongly on word order. Frequency adverbs usually go before a lexical verb but after be.
Subject + adverb + lexical verbSubject + be + adverbVerb + object + manner/place/timeFormal emphasis can place a negative or restrictive adverbial first and invert the auxiliary and subject.
Never have I...Rarely do they...Not only did she...The passive keeps the tense in the auxiliary be while the main verb stays in the past participle form.
is done / was done / has been done / will be done / is being doneEnglish often avoids repetition by omitting recoverable words or replacing them with forms such as one, do, so and neither.
I can swim and she can too.the red oneI think so.Words such as each, every, either and neither are normally singular when they are the grammatical head of the subject.
Each/Every + singular noun + singular verbEither/Neither + singular verbExamples come from the editable lesson database and change order each load.
Questions and answer choices are randomized for every new attempt.
Intermediate Grammar B1
In this article, Intermediate Grammar B1 learners study non-defining relative clauses.
You will learn how essential relative clauses identify exactly which noun you mean.
The key question is: Is the relative clause necessary to identify the noun?
The main rule to remember is: A main clause can stand alone. A dependent clause needs another clause to complete the sentence.
You will study relative clauses without commas that define people and things.
By the end, you should be able to write defining relative clauses without unnecessary commas.
Clauses are groups of words with a subject and verb. They can act like nouns, adjectives, or adverbs, and they help writers combine ideas precisely.
Non-Defining Relative Clauses looks specifically at non-defining relative clauses. At this level, the goal is to explain relationships between ideas and avoid common intermediate mistakes.
As you read, keep one question in mind: Is the relative clause necessary to identify the noun? This question will help you connect the rule to meaning instead of memorizing the form alone.
You will see relative clauses without commas that define people and things, then practice the topic through corrections, short tasks, and a final review.
This section breaks non-defining relative clauses into practical rules. Read each rule, study the examples, and notice how the form supports the meaning.
Relative clauses describe nouns and often begin with who, which, that, whose, where, or when.
Noun clauses act like nouns and can be subjects, objects, or complements.
Adverb clauses show time, reason, condition, contrast, purpose, or result.
The examples below focus on non-defining relative clauses. Read the sentence, then read the note so you can see why the grammar choice works.
| Use | Example | Why It Works |
|---|---|---|
| Core pattern | The woman who called is my aunt. | This example connects to non-defining relative clauses and shows relative clauses without commas that define people and things. |
| Natural use | The book that I bought is useful. | This example connects to non-defining relative clauses and shows relative clauses without commas that define people and things. |
| Meaning check | This is the city where I was born. | This example connects to non-defining relative clauses and shows relative clauses without commas that define people and things. |
| Daily English | What she said was important. | This example connects to non-defining relative clauses and shows relative clauses without commas that define people and things. |
| Careful writing | I know that he is honest. | This example connects to non-defining relative clauses and shows relative clauses without commas that define people and things. |
| Question form | The question is whether we can finish. | This example connects to non-defining relative clauses and shows relative clauses without commas that define people and things. |
| Formal style | Call me when you arrive. | This example connects to non-defining relative clauses and shows relative clauses without commas that define people and things. |
| Review sentence | I stayed home because I was tired. | This example connects to non-defining relative clauses and shows relative clauses without commas that define people and things. |
Non-defining relative clauses becomes more useful when it appears inside connected writing, not only in isolated examples. Try using the topic in a short message, a description, a comparison, or an explanation.
A strong example should answer the article question: Is the relative clause necessary to identify the noun? If your sentence answers that question, the grammar is doing real work.
These mistakes show what can go wrong with non-defining relative clauses. Compare the wrong sentence, the correction, and the reason before you write your own examples.
| Common Mistake | Correction | Why |
|---|---|---|
| The man which called is here. | The man who called is here. | Use who for people in relative clauses. |
| I know what does she want. | I know what she wants. | Use statement word order in noun clauses. |
| Although it was late. We continued. | Although it was late, we continued. | A dependent clause needs a main clause. |
Use these exercises after reading the article. They are designed around non-defining relative clauses, so each task should help you use the topic in a specific way.
Write a short paragraph of five to seven sentences that includes non-defining relative clauses. After writing, highlight the grammar pattern and explain how it answers this question: Is the relative clause necessary to identify the noun?
Answer these questions to check whether you can recognize and use non-defining relative clauses without relying only on memory.
This topic is useful because it helps you make a specific grammar choice instead of relying on translation or habit.
Before you leave this article, check whether you can answer this question clearly: Is the relative clause necessary to identify the noun?
If the answer feels automatic, try using non-defining relative clauses in a new sentence about your own life, work, studies, or opinions.
Next step: Write five sentences beginning The person who or The thing that.
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begin an activity eagerly and without delay
Once everyone is ready, we can dive in.
enter a building or place illegally or by force
Someone tried to break in last night.
start or activate a machine, device, or system
Can you turn on the system?
land on the ground, especially an aircraft
The plane should touch down at noon.
find information or an object by searching, often something hidden or forgotten
The reporter managed to dig up new evidence.
support a person, claim, system, or copy of data
Make sure you back up your files.
make an image or view appear farther away and show a wider area
You can zoom out to see the whole page.
attack and seriously hit or injure someone
The police arrested men accused of trying to beat up a victim.
improve or change a situation significantly
The company hopes to turn around the situation this year.
return to a place or previous situation
We should head back before it gets dark.
save money gradually for a future purpose
We are trying to save up for a vacation.
match or look good together with something
This shirt should go with those pants.
visit someone informally for a short time
Why don’t you stop by after work?
die; a polite expression
A person may pass away peacefully in old age.
put clothing or an accessory on your body
You should put on a jacket before going outside.
lose consciousness for a short time
A person can black out from extreme heat.
speak more loudly or express an opinion openly
Could you speak up so everyone can hear?
listen secretly or deliberately to a conversation not meant for you
Someone was listening in on our conversation.
experience or endure a difficult process or period
She had to go through a difficult year.
take control or responsibility from someone else
She will take over the department next month.