The house is dirty because it since they moved out.
A.doesn’t clean | B.isn’t cleaned | C.hasn’t cleaned | D.hasn’t been cleaned |
The buses, ____were already full, were surrounded by an angry crowd.
A.most of them | B.most of which | C.which most | D.that most |
Can you solve such problems ___raised by the audience?
A.what were | B.as were | C.that were | D.which were |
We often think of the days ___we spent together on the island.
A.when | B.which | C.in which | D.during which |
Air, _ __we breathe every day, is around us all the time.
A.that | B./ | C.which | D.it |
The radio set __ _ last week has been out of order.
A.I bought | B.I bought it | C.which I bought it | D.what I bought |