Topics: Tenses Usage
The scientist _____ solutions to clean polluted rivers when she discovered a breakthrough.
A. researched
B. was researching
C. had researched
D. is researching
Select your answer:
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Grammar › ViewWhat is the complete subject of the sentence, “The pet store is busy on Saturday.”?
A. The pet
B. The store
C. The pet store
D. Busy on Saturday
Perfect Verb Tenses › View
Isla has been hitting the books hard for her exams! Which sentence captures her study habits in the present perfect tense?
A. I will have finished my homework by tomorrow.
B. I have been studying for two hours.
C. I studied for two hours yesterday.
D. I will study for two hours tomorrow.