题目内容
The country has already sent up three unmanned spacecrafts, the most recent at the end of last March.
A. has been launched B. having been launched
C .being launched D. to be launched
B
解析:
略
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题目内容
The country has already sent up three unmanned spacecrafts, the most recent at the end of last March.
A. has been launched B. having been launched
C .being launched D. to be launched
B
略