一般照明用电为(),通过人体的安全电压为()。
参考答案:220V、36V
John,together with some of American soldiers who sent to Iraq, killed in a bomb explosion.
A.were;were
B.was;was
C.were;was
D.was;were
It's over twenty years ______ we met last. Can we recognize each other when we meet at the airport?[ ]
A. before
B. until
C. since
D. once