Question

The country has already sent up three unmanned spacecraft, the most recent ________ at the end of last March.

A．has been launched	B．having been launched
C．being launched	D．to be launched

Answer 1

B

這題考查獨(dú)立主格結(jié)構(gòu)，結(jié)構(gòu)是：名詞+非謂語(yǔ)，此句前后句沒(méi)連詞，只有逗號(hào)是不能連接兩個(gè)句子的,所以后邊the most recent ______ at the end of last March就是獨(dú)立主格的形式了，在句中做伴隨狀語(yǔ)，又因?yàn)槭虑榘l(fā)生在過(guò)去，所以用現(xiàn)在分詞完成時(shí)。選B。