题目内容

-The two astronauts had been trained for long before they flew to space.

 -Oh,they     quite a lot of difficulties

    A.might go through                       B.may go through

    C.should have gone through           D.must have gone through

练习册系列答案
相关题目

违法和不良信息举报电话:027-86699610 举报邮箱:58377363@163.com

精英家教网