In this article, Elementary Grammar A2 learners study gerunds vs infinitives.

You will learn how to choose between verb-ing and to plus base verb after another word.

The key question is: Does this first verb need a gerund, an infinitive, or either form with a meaning change?

In this article, Elementary Grammar A2 learners study modal verbs.

You will learn how to use modal verbs in clear English sentences.

The key question is: How can I use modal verbs correctly without guessing?

The main rule to remember is: Use modal verb plus the base verb without to, except for semi-modals such as ought to and have to.

In this article, Elementary Grammar A2 learners study can and could.

You will learn how can and could express ability, possibility, permission, and polite requests.

The key question is: Does the sentence talk about ability now, ability in the past, possibility, or politeness?

In this article, Elementary Grammar A2 learners study may and might.

You will learn how may and might express possibility and polite permission.

The key question is: How certain is the speaker, and is the sentence formal or neutral?

In this article, Elementary Grammar A2 learners study must and have to.

You will learn how must and have to express strong obligation, rules, and necessity.

The key question is: Is the obligation personal, official, external, or logical?

In this article, Elementary Grammar A2 learners study shall and should.

You will learn how should gives advice and shall appears in offers, suggestions, and formal language.

The key question is: Is the sentence giving advice, making an offer, or sounding formal?

In this article, Elementary Grammar A2 learners study will vs would.

You will learn how will and would differ in certainty, future meaning, politeness, habit, and imagined situations.

The key question is: Is the sentence real and future, polite, habitual in the past, or hypothetical?

In this article, Elementary Grammar A2 learners study ought to.

You will learn how ought to gives advice, expectation, or moral recommendation.

The key question is: Is the speaker saying what is right, sensible, or expected?

The main rule to remember is: Use modal verb plus the base verb without to, except for semi-modals such as ought to and have to.

In this article, Elementary Grammar A2 learners study need and needn't.

You will learn how need works as a main verb and as a modal-like verb in negatives.

The key question is: Does need behave like a normal verb or a modal in this sentence?

In this article, Beginner to Elementary Grammar A1 learners study adverbs of frequency.

You will learn where to place always, usually, often, sometimes, rarely, and never.

The key question is: How often does the action happen?

The main rule to remember is: Place the adverb where it clearly connects to the word or idea it modifies.