Auxiliary verbs
Auxiliary verbs, also called helping verbs, are used with a main verb to create compound verb forms.
verbs
Contractions with the verb BE
The simple present of the verb BE can be contracted in two ways: with a subject pronoun or with the negative adverb not
Contractions with the verb DO
The simple present and simple past of the auxiliary verb DO are frequently contracted with the negative adverb not.
Contractions with the verb HAVE
This lesson explains how to make contractions with the verb HAVE and a subject pronoun or the negative adverb not.
Could have vs Could of
The phrase could have refers to something that was possible but did not occur in the past. In informal speech, it is contracted to could've, not could of.
Future
This lesson introduces the various forms English uses to indicate the future.
Introduction to verbs
Verbs are the words in a sentence that indicate an action, a state of being, or possession.
Irregular verbs
A list of the most common irregular English verbs, including their simple past conjugations and present and past participles.
Modal verbs
This lesson explains the grammar of modal verbs and where they are placed in a sentence or question.
Modal verbs (part 2)
This lesson explains the meaning of each modal verb and provides example sentences.
Negation and the verb BE
The verb BE can be negated with negative adverbs, adjectives, and prefixes.
Negation and the verb DO
This lesson explains one of the very important roles of the verb DO: the formation of negative phrases.
Past participle
The past participle is a verb form that indicates a completed action. It is used in perfect aspects, adverb clauses, and the passive voice.
Past perfect
The past perfect, or pluperfect, is a compound verb form which requires two verbs: had and a past participle.
Past perfect progressive
The past perfect progressive, also called the pluperfect progressive is a compound verb form. It requires three verbs: had + been + verb+ing.
