[ Tenses ]
The fossil fuels ____ air pollution significantly last century.
A. contributed
B. contribute
C. is contributing
D. will contribute
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The Past SimpleComparisionModals and Active and Passive VoicePresent Simple PassiveInfinitive and GerundsCorrelative ConjunctionFuture Tense - will and going toAdjectives Ed and IngContinuous and Perfect TensesArticleOther quiz:
Passive Voice › ViewUp to now, the equipment ____ regularly, but from now on, we ____ it before every outing.
A. wasn’t checked – are checking
B. hasn’t checked – will be checking
C. hasn’t been checked – are going to check
D. isn’t being checked – should be checked
Basic Grammar › View
The plane arrived (…) the airport just on time.
A. on
B. of
C. at
D. by