Either you or Tom _____ going to Beijing tomorrow. [ ]
A. are
B. is
C. was
D. were
答案:B
计算(-1)2007-(-1)2006的结果是[ ]
A.0
B.2
C.-1
D.-2
The book __________ I put on the desk just now is gone.[ ]
A. who
B. that
C. why
D. where