问题

___ there are living creatures in the outer space as those on Earth hasn’t been proved until now

A:How
B:When
C:Where
D:Whether

正确答案是：

同类题型

ung tribal man helped Mrs. Davidsonfind her way back, in return for________medical equipment was offered to him bythe latter.

e me, can you tell me how I can get to thenearest market, please—Mm, let me think Oh, yes! It’s past ______postoffice , next to ______bank

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Shall I use your red ink? —It is a pity that it_____. I will get some.

He didn’t tell us the truth ___ elevent o’clock last night