单项选择题

They recommended () smaller heating and cooling systems.

A. to use
B. to be used
C. being used
D. using

<上一题目录下一题>

热门试题

单项选择题

Mary was (surprised to) realize that it was (us), her old (school friends), (calling) her from Paris.()

A. surprised to
B. us
C. school friends
D. calling

单项选择题

We see lighting (before we hear) the thunder (because) sound travels (more slowly) than (light is).()

A. before we hear
B. because
C. more slowly
D. light is

相关试题