(2011年南通一模)________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

解析：選D�？疾槊~性從句。句意：外太空是否存在像地球上一樣的生物還不能確定。whether引導(dǎo)主語從句。

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 (2011年南通一模)—Where have you been all day?

—I________some former classmates and I couldn’t get back until it was dark.

A．have met                      B．met

C．would meet                  D．had met

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