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【判断题】
PN结加正向电压时,内电场和外电场方向相反而截止。A.
正确
B.
错误
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【单选题】_________ first time I met him in his office, he shook me by _________ hand warmly and then introduce himself to me.
A.
The; 不填
B.
The; the
C.
The; a
D.
A; 不填
【简答题】药材名(),根头部瘤状突起叫()
【单选题】I have no experience related to _______, since it's the first time for me to handle such a problem. [ ]
A.
call upon
B.
live on
C.
take on
D.
draw upon
【单选题】One of them told me, “This is the first time I ________ to the capital to attend the flag-raising ceremony.”
A.
came
B.
come
C.
have come
D.
had come
【单选题】Please show me ______ to send an e-mail, John. It's the first time for me to do it. [ ]
A.
how
B.
what
C.
when
D.
where
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