Question

what are modal auxiliaries?

Answer 1

Modal auxiliary verbs include: can, could, may, might, must, ought, shall, should, will, and would. These verbs - which never change forms the way most other verbs do - indicate possibility, capability, necessity, or willingness. ... Modal auxiliary verbs can also express a negative condition

Answer 2

modal verb is a type of verb that is used to indicate modality – that is: likelihood, ability, permission and obligation. Examples include the English verbs can/could, may/might, must, will/would and shall/should.
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