Question

（2003年上海卷，39）Generally speaking ,        according to the directions , the drug has no side effect .

A．when taking               B．when taken        C．when to take         D．when to be taken

Answer 1

B

解析:

當(dāng)分詞的邏輯主語也就是主句的主語，這時(shí)可以省去邏輯主語和be動(dòng) 詞.現(xiàn)在分詞表示主動(dòng)和進(jìn)行，而過去分詞表示被動(dòng)和完成。在這個(gè)句子中， 其實(shí)是when the drug is taken,省去了the drug is，the drug 和take是被動(dòng)關(guān)系．