Minister Bill De Blasio     in office fewer than 48 hours when he came face to face with his biggest challenge in his life.
#63755
A
has been
B
had been
C
would be
D
is
推荐题目
 Up to now, our society ________ with limited living space and a shortage of natural resources.
#63760
A
has been challenged
B
is being challenged
C
is challenging
D
has challenged
I wonder why Jenny ____ us recently. We should have heard from her by now. 
#63792
A
hasn’t written
B
doesn’t write
C
won’t write
D
hadn’t written
 It’s reported that in the past 50 years around 80 percent of Beijing’s courtyard houses ______.
#63767
A
had wiped out
B
have wiped out 
C
have been wiped out 
D
had been wiped out
 Tom ________ in the library every night over the last three months.(2011·北京)
#63775
A
works
B
worked
C
has been working
D
had been working