This vase ________ perfect but for a few small holes in its base.
A．would have been B．should have been
C．shall be D．would be
Tom sacrificed his personal life ________ he could get ahead in his career.
A．in case B．as if
C．so that D．only if
There is still a strong argument ________ mobile phones are a particular risk to children.
A．when B．which
C．that D．what
Students ________ remain in their seats until all the papers have been collected.
A．shall B．might
C．could D．will
John Wood，an Internet blogger，discovered that Samsung ________ for not protecting its workers from a dangerous chemical used on its phones.
A．had criticized B．had been criticized
C．was criticized D．was criticizing
The sign says that children are admitted only if ________ by an adult.
A．to be accompanied B．accompanying
C．accompanied D．to accompany
