单项选择题

Plastics ______ many conventional materials.

A．has take the place of
B．have taken place
C．have taken the place of
D．has taken place
<上一题 目录 下一题>
热门 试题

单项选择题
We ______ that he is quite untrust--worthy.
A．have found
B．have discovered
C．have invented
D．have looked for
单项选择题
A part of his story ______ true.
A．are
B．is
C．will
D．is being
相关试题