If the new safety system _______ to use, the accident would never have happened.
| A． |
had been put |
B． |
were put |
C． |
should be put |
D． |
would be put |
His comprehensive surveys have provided the most______ statements of how, and on what basis, data are collected.
| A． |
explicit |
B． |
ambiguous |
C． |
original |
D． |
arbitrary |
Many businesses started up by college students have______thanks to the comfortable climate for business creation.
| A． |
fallen off |
B． |
taken off |
C． |
turned off |
D． |
left off |
Dashan, who ______crosstalk, the Chinese comedic tradition, for decades, wants to mix it up with the Western stand-up tradition.
| A． |
will be learning |
B． |
is learning |
C． |
had been learning |
D． |
has been learning |
In art criticism, you must assume the artist has a secret message______within the work.
| A． |
to hide |
B． |
hidden |
C． |
hiding |
D． |
being hidden |
If it ______for his invitation the other day, I should not be here now.
| A． |
had not been |
B． |
should not be |
C． |
were not to be |
D． |
should not have been |