English modal verbs

The modal verbs of English are a small class of auxiliary verbs used mostly to express modality (properties such as possibility, obligation, etc.). They can be distinguished from other verbs by their defectiveness (they do not have participle or infinitive forms) and by the fact that they do not take the ending -(e)s in the third-person singular.

The principal English modal verbs are can, could, may, might, must, shall, should, will and would. Certain other verbs are sometimes, but not always, classed as modals; these include ought, had better, and (in certain uses) dare and need. Verbs which share some but not all of the characteristics of the principal modals are sometimes called "semimodals".

The verbs customarily classed as modals in English have the following properties:

The following verbs have all of the above properties, and can be classed as the principal modal verbs of English. They are listed here in present–preterite pairs where applicable:

Note that the preterite forms are not necessarily used to refer to past time, and in some cases they are near synonyms to the present forms. Note that most of these so-called preterite forms are most often used in the subjunctive mood in the present tense. The auxiliary verbs may and let are also used often in the subjunctive mood. Famous examples of these are "May The Force be with you," and "Let God bless you with good." These are both sentences that express some uncertainty, hence they are subjunctive sentences.

The verbs listed below mostly share the above features, but with certain differences. They are sometimes, but not always, categorized as modal verbs. They may also be called "semimodals".

Other English auxiliaries appear in a variety of different forms and are not regarded as modal verbs. These are:

For more general information about English verb inflection and auxiliary usage, see English verbs and English clause syntax. For details of the uses of the particular modals, see § Usage of specific verbs below.

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