单项选择题

The promise of finding long-term technological solution ________the problem of world food safety seems difficult to fulfill.

A．to
B．for
C．of
D．at
<上一题 目录 下一题>
热门 试题

单项选择题
It was not until she arrived at the airport ________she realized she had forgotten her passport.
A．and
B．when
C．where
D．that
单项选择题
The professor, ________whether anyone would come to help him, had to prepare for the experiment by himself.
A．did not know
B．having not known
C．had not known
D．not knowing
相关试题