英文法、8.助動詞

 8.助動詞

助動詞：幫助動詞形成各種時態、語氣、語態、疑問/否定句

助動詞：be動詞：進行式或被動語態 (am, are, is, was, were)

              過去 / 現在 / 未來  進行式   =     were / are / will be  +  Ving  + 現在分詞

        *被動語態 =  (am, are, is, was, were)  +  過去分詞

                    That medicine is best taken after meals.

                    This story was written by Helen

助動詞：have ：完成式  (have, has, had)

                  完成式： (have, has, had)  + 過去分詞     

                                                                I have finished my homework.

                 完成進行式：(have, has, had)  been + 現在分詞    

                                                                It has been raining on and off since last night.

                 完成被動式： (have, has, had)  been + 過去分詞     

                                                              The contract had been signed before we got there. 

助動詞：do： (do, does, did)

                第三人稱、單數、現在式，助動詞用does

                        Paul does not like mathematics.

                疑問句： (do, does, did) + 主詞+ 動詞原型

                        Does he like pop music?

                否定句： (do, does, did) + 動詞原型

                      Your opinion about what is right for you doesn’t mean that it is right for others.

                代替前面已提過的動詞或當主要動詞

                    The students ran out of the classroom and so did the teacher.

                    What do you do in your free time?

                加强語氣：倒裝   Never did I stop loving you.

情態助動詞：置於主要動詞之前，幫助主要動詞來表達意願   S+情態助動+動詞原型

                            It may rain this afternoon. You ought to wear a rain jacket.

情態助動詞 + 完成式的特別意思

    should have     +     過去分詞    （被期待卻沒有發生）
    shouldn't have +     過去分詞    （不被期待卻發生了）
    must  have       +     過去分詞     （肯定發生了）
    can't have        +      過去分詞     （絕對沒有發生）
    might have      +      過去分詞     （可能發生）

            Someone must have taken my umbrella; it’s gone!

             Mike can’t have left the office yet because his car is still there.

            轉述句裡 can, may, will, shall 分別要改成 could, might, would, should

                            Bob won't be here to play bridge tonight. But he told me he would come.

動詞片語：動詞與多個助動詞形成。表時態、語態、疑問否定

                David should have known the answer to the math question. 

7.主被動    ↼   8.助動詞    ⇀ 9.假設語氣