2016英語四級常用語法精選(4)

Ⅱ 非謂語動詞
    不定式
    形式
    主動形式 被動形式
    一般式 to do to be done
    完成式 to have done to have been done
    進行式 to be doing
    完成進行式 to have been doing
    完成式: 不定式的一般形式所表示的動作, 通常與主要謂語表示的動作(狀態(tài))同時(或幾乎同時)發(fā)生, 或是在它之后發(fā)生. 假如不定式所表示的動作, 在謂語所表示的動作(狀態(tài))之前發(fā)生, 就要用不定式的完成式。
    I am glad to have seen your mother (= I am glad I have seen your mother).
    (比較: I am glad to see you.)
    He is said to have written a new book about workers.
    He pretended not to have seen me.
    進行式: 如果主要謂語表示的動作(狀態(tài))發(fā)生時, 不定式表示的動作正在進行, 這時要用不定式的進行式。
    You are not supposed to be working. You haven't quite recovered yet.
    We didn't expect you to be waiting for us here.
    He pretended to be listening attentively.
    完成進行式: 在謂語所表示的時間之前一直進行的動作, 就要用不定式的完成進行式.
    The struggle was known to have been going for twenty years.
    We are happy to have been working with you.