八年級英語下冊知識點總結
he wrote the letter. →the letter was written by him.
4）主動句變被動句的基本句式：
a) 主：主語+助動詞（情態動詞）+謂語+賓語
被：主語（原賓語）+助動詞（情態動詞）+be+動詞過去分詞+by+原主語
如，we will help him.→he will be helped by us.
b) 主：主語+動詞短語+賓語
被：主語（圓賓語）+be+動詞短語的過去分詞+by+原主語
如，they looked after the babies.→the babies were looked after by them.
c) 主：主語+謂語+間接賓語+直接賓語
被：主語（間接賓語）+be+動詞過去分詞+原直接賓語
主語（直接賓語））+be+動詞過去分詞+to(for)+原間接賓語+（by+原主語）
如，we gave him some magazines.→he was given some magazines.
some magazines were given to him by us.
【注意】一般將主動句中表示人的間接賓語變為被動句中的主語。
d) 主：主語+謂語+賓語+賓語補足語
被：主語（原賓語）+be+過去分詞+原賓語補足語
如，they elected him their monitor.→he was elected their monitor.
【注意】如果主動句中賓語補足語是不帶to的不定式，變成被動語態后一般要加to.
i saw him go to the church.→he was seen to go to the church.
【擴展】一般在以下幾種情形時，需要使用被動語態。
1） 不知道動作的執行者，只知道動作的承受者時。
when we got there, the room had been cleaned already.
2） 不必要說出或出于禮貌不便說出動作的執行者時。
i was told that you were not honest enough.
3）有必要突出或強調動作的承受者時。
you were asked to answer this question.
16.if與whether:if和whether均可用于賓語從句中，意為“是否”；if用于條件句中，表示“如果”，不能和or連用；whether常與or連用，表示兩種條件或情況。
【擴展】if not..如果不是…,表示驚訝或憎惡等情緒；if only意為“若…那就好了，我多么希望…”相當于how i wish；only..if..意為“決不…除非…”
if it hadn’t been for the doctor’s care, i should not be speaking to you now.如果不是醫生的照顧，我現在就不會和你說話了。
if only he arrives in time!若他及時到達就好了。
i’ll only come if you promise me that you won’t invite henry.除非你答應不請亨利，否則我不會來。
◆unit 7 would you mind turning down the music?
知識點：
1. 基本用法：1）would you mind doing?=do you mind doing..?“你介意…?” “請你…好不好？”是一種比較客氣的表達方式。2）如果要表示“請你不要做…好嗎？”只需在doing 前面加not.應答用語：1）如果同意表示不介意時，可用如下用語來表達：certainly not.; of course not.;no,not at all.;not at all.“好，可以”2）如果不同意表示介意時，常用“sorry.”“i’m sorry, but…”及陳述某種理由來表示拒絕或反對。；這一句型中的邏輯主語只能是談話的對方you，如果想要對方允許自己做某事，可以用 “would you mind my doing..?句型。