[ Modals of Necessity and Suggestion ]
I think the most important thing to stop similar things from ever happening again is to seize every opportunity you (4) ( can / ought to ).
A. can
B. ought to

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Adverb of MannerWh- Questions Present Simple TensePast Simple and Past Continuous TensesThird ConditionalsNoun, Quantifiers and SuffixesModals of ObligationTime Clauses of FutureUnderstanding Product Packaging and TensesPresent Progressive or Present SimplePrepositions and Preposition PhrasesOther quiz:
Conjunctions › ViewI will cook dinner _______ you do the dishes.
A. when
B. as long as
C. while
D. after
Modals › View
I……… swim across the river when I was young.
A. Can
B. Could