题目内容

[A] to be doing
[B] with doing
[C] to do
[D] of doing

查看答案

搜索结果不匹配？点我反馈

更多问题

We shall probably never be able to _____ the exact nature of these sub-atomic particles.
[A] assert
[B] impart
[C] ascertain
[D] notify

[A] respond
[B] return
[C] retort
[D] reply

[A] on
[B] from
[C] at
[D] about

That sound doesn’t _____ in his language so it’s difficult for him to pronounce.
[A] happen
[B] take place
[C] occur
[D] run