Q13
EnglishVerbs, Tenses & Agreement
Fill in the modal auxiliaries as required: I _____ swim. [Ability]
- a.should
- b.must
- c.can
- d.don't
Answer: (C) can
'Can' is the modal auxiliary that expresses ability or capacity, exactly what the hint [Ability] asks for; its past form is 'could' and its near-equivalent is 'be able to'. 'Should' expresses advice or duty, 'must' expresses necessity or strong obligation, and 'don't' is the negative of the auxiliary 'do', not a modal. Quick chart of modal functions for the exam: can/could = ability, may/might = permission or possibility, must = compulsion or logical certainty, should/ought to = advice, will/would = willingness or habit, need not = absence of necessity.