Rephrase the sentence in passive voice in present perfect continuous tense: He has been studying for hours.
A. Studying has been being done by him for hours.
B. He has been studying for hours by him.
C. For hours, he has been studying.
D. He has been studying for hours since.

Random Topics:
1st and 2nd ConditionalsNouns, Pronouns, Antecedents, and Singular and PluralGrammar, adverbs of frequency placementAction VerbObject PronounRun-On SentencesSimple Present and Present Continuous TenseComparativeFirst ConditionalConnectorsOther quiz:
Verb Tenses › ViewBy this time next year, Brian ————— a doctor.
A. will become
B. will have become
C. will have became
Grammar › View
Jane is talking to Mike, who has just helped her with her luggage.
Jane: “______”
Mike: “It’s my pleasure.”
A. It’s too heavy
B. Thanks a lot
C. It’s not my duty
D. Welcome back
Subject Verb Agreement › ViewMost of the rooms in the hotel (have / has) air-conditioning.
A. have
B. has
Grammar › View
Look at the picture, and decided what is the correct description for each one.
A. She is an old woman with gray hair.
B. She is a young girl with long hair.
C. He is a middle age bald men.