It just isn’t fair____________I was working as a waiter last month;my friends were lying on the beach.
A.whenever
B.though
C.for
D.while
第1题:
A、haven’t
B、hasn’t
C、isn’t
D、aren’t
第2题:
There must be something wrong with my computer,()there?
A. mustn't
B. needn't
C. isn't
第3题:
– Nice weather, isn't it? – ( ).
A. I'm not sure
B. You know it well
C. Yes, it is
D. Yes, it isn't
第4题:
若 E[X(t1)] =mx(t1),E[ Y(t2)] =my(t2),E[X(t1) Y(t)2] =mx(t1)my(t2),则随机过程X(t)与Y(t)。
A.不相关
B.相关
C.正交
D.独立
第5题:
____ I?know,?there?isn’t?such?a?word?in?English.
A、As much as
B、So far as
C、As long as
D、As soon as
第6题:
22. Ben,_______ climb the tree. It is very dangerous.
A.doesn't
B.not
C.don't
D.isn't