21. We ________ at home since last October. 

has studied

studies

have studied

studied

22. Some children _______ the online classes. 

are enjoying

is enjoying

was enjoying

were enjoying

23. I have tried everything to finish my assignment. 

present perfect tense

past perfect tense

future perfect tense

simple present tense

24. We had waited for a year for this chance to go on vacation.

present perfect tense

past perfect tense

simple present tense

present progressive

25. She has been doing online class since October 2020. 

present perfect progressive tense

present progressive tense

present perfect tense

simple present tense

nonsense answer reported

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