不定式或現(xiàn)在分詞的動(dòng)作若發(fā)生在謂語動(dòng)詞的動(dòng)作之前,用完成式(過去分詞沒有完成式),否則,就用一般式。若與謂語動(dòng)作同時(shí)發(fā)生,并強(qiáng)調(diào)正在進(jìn)行的情景或持續(xù)性,可用不定式的進(jìn)行式(現(xiàn)在分詞和過去分詞均沒有進(jìn)行式)。如:
Having failed twice, he didn’t want to try again. 他已經(jīng)失敗了兩次,不想再試了。
He came in, followed by his secretary. 他走了進(jìn)來,后面跟著他的秘書。
He seems to have caught a cold. 他似乎感冒了。
He seems to be saying something. 他似乎在說什么。
2. 非謂語動(dòng)詞的語態(tài)
不定式或-ing 形式與其邏輯主語若是主動(dòng)關(guān)系,用主動(dòng)式;若是被動(dòng)關(guān)系,用被動(dòng)式。如:
Who is the woman being operated on? 正在動(dòng)手術(shù)的女人是誰?
Did it need to be done so soon? 這事需要這么快就做嗎?
注:(1) 過去分詞沒有被動(dòng)式。(2) 有些非謂語動(dòng)詞要主動(dòng)式表示被動(dòng)意義。