Passive voice

Passive voice
Câu 1 :
The robbers ......... since last Monday.
A.have arrested B.have been arrested C.were arrested D.are arrested
Câu 2 :
Did they ........ this house in 1990?
A.build B.was built C.has built D.built
Câu 3 : 
Gold ........... in California in the nineteenth century.
A.was discovered B.has been discovered C.discovered D.are discovered
Câu 4 : 
My son ........ games for two hours.
A.played B.is played C.has played D.has been played
Câu 5 :
Meals ........ by Hoa every day.
A.cooks B.cooked C.has cooked D.are cooked
Câu 6 :
My father waters this flower every morning.
=> This flowers
Câu 7 :
John invited Liz to his birthday party last night.
=> Liz
Câu 8 :
Our teacher have already explained the English drama.
=> The English
Câu 9 :
Did Mary buy this beautiful dress? 
=> Was
Câu 10 :
The German didn't build this factory during the Second World War.
=> The factory
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