单项选择题

We must ______ that the experiments are carried out as rigidly as possible.

A．ensure
B．assure
C．insure
D．secure
<上一题 目录 下一题>
热门 试题

单项选择题
Their relationships with their parents have been so ______ that they are no longer able to communicate.
A．restless
B．distant
C．tight
D．strained
单项选择题
She was late yesterday because the rear tire was ______ by a nail and went flat as she was on the way here.
A．pierced
B．punched
C．thrust
D．penetrated
相关试题