[ 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
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ApologizingCoherent Sentence with Correct Grammar StructureSimple, Compound, Complex SentencesModals and AdvicePresent Simple and Present Continuous TenseReported Speech and Reported QuestionsPast Perfect & Past Simplemust/shouldPrepositions of Place & TimeKnee AnatomyOther quiz:
Tenses › ViewThe teacher …… and the students ……. in the class
A. is stands / are sit
B. standing / sitting
C. is standing / are sitting
D. are standing/ is sitting
Grammar › View
Please talk …. . I don’t want the baby wake up.
A. slowly
B. quietly
C. fast
Grammar › ViewWhich of the following is a proper noun?
A. city
B. dog
C. Paris
D. book
Grammar › View
Choose the correct conjunction to complete the sentence:
I couldn’t hear _____ could I see the speaker.
A. and
B. nor