单项选择题

The existence of oil wells ______ for a long time. 04版－45

A．been known
B．was known
C．had been known
D． has been known
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单项选择题
China is larger than ______.
A．any countries in Asia
B．any other countries in Asia
C．all countries in Asia
D．Japan and Thailand as well as Asia
单项选择题
Each of us ______ thinking the same thing.
A．am
B．is
C．are
D．were
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