亚洲免费av电影一区二区三区,日韩爱爱视频,51精品视频一区二区三区,91视频爱爱,日韩欧美在线播放视频,中文字幕少妇AV,亚洲电影中文字幕,久久久久亚洲av成人网址,久久综合视频网站,国产在线不卡免费播放

        ?

        情態(tài)動詞must的用法

        2010-05-29 07:17:12吳懷霞
        關(guān)鍵詞:否定句答語時用

        吳懷霞

        must的用法比較多,而且難掌握,現(xiàn)歸納如下;

        1. must的意義

        (1)表示責(zé)任,義務(wù), 意為“必須”。如:

        You must tell me the truth.

        (2)強(qiáng)調(diào)語氣的肯定,意為“一定要”。如:

        I must ask you about your family.

        (3)表示推測,意為“想必”。如:

        He must be at home; the light is on.

        2. must 的時態(tài)

        must只有一種形式, 在將來時里,可用must, 也可用 shall(will) have to。如:

        I must be at home tomorrow.

        I shall have to go there some day.

        must 一般不用于過去時態(tài),它的過去式常用had to代替。如:

        I had to go there yesterday.

        但在下列情況下must也可用過去時:

        (1)在間接引語中。如:

        He said that he must talk with his teacher.

        He decided that he must try to be on the side of the winner.

        I said you mustnt go there.

        (2)作推測解時。如:

        He must have gone to Beijing yesterday.

        (3)作“偏偏”解時。如:

        Just when they were about to go there, they must catch a bad cold.

        3. must的否定式及其答語

        (1)當(dāng)must意為“必須”時否定式是neednt。如:

        You must pay the money, but you neednt do so at once.

        Must I finish my homework now?

        Yes, you must./No, you neednt.

        其否定也可用dont have to。如:

        You must be back by 12 oclock. 變?yōu)榉穸ň鋺?yīng)是:

        You neednt be back by 12 oclock. 或 You dont have to be back by 12 oclock.

        (2)當(dāng)要表達(dá)“絕對不可,不許”時,其否定式是mustnt。如:

        You mustnt do that.

        You mustnt smoke, must you?

        I mustnt let anyone know.

        I must save money, mustnt I?

        (3)表示“推測”時 其否定式為cant。如:

        He must be there.

        He cant be there.

        (4)——May I come in?

        ——No, you mustnt.

        4. must 與 have to

        一般情況下可以通用。如:

        You must(have to) do as you are told.

        但:(1)表示主觀上認(rèn)為的責(zé)任或義務(wù)時用must。如:

        We must try our best to do it.

        (2)表示命令時用must。如:

        You must answer my question in English.

        (3)表示客觀條件不得不如此時,用 have to。如:

        He missed the bus and had to walk home.

        (4)must的否定式表示“絕對不可,不許, 禁止”,have to的否定式表示“不必”。如:

        You mustnt smoke in class.

        You dont have to go there.

        猜你喜歡
        否定句答語時用
        離心機(jī)轉(zhuǎn)速的寫法及相對離心力的正確表示
        離心機(jī)轉(zhuǎn)速的寫法及相對離心力的正確表示
        離心機(jī)轉(zhuǎn)速的寫法及相對離心力的正確表示
        can have done用法小結(jié)
        do和does都是“活雷鋒”
        新目標(biāo)英語七年級(上)Unit8 STEP BY STEP隨堂通
        關(guān)于數(shù)字的俗語連線
        Unit 12 STEP BY STEP 隨堂通
        Unit 7 STEP BY STEP 隨堂通Section A
        學(xué)寫雙重否定句
        欧美嫩交一区二区三区| 亚洲av精品一区二区三| 99久久婷婷国产精品综合网站| 国产免费牲交视频| 999久久久国产精品| 欧美成人www免费全部网站| 热门精品一区二区三区| 国产精品久久久免费精品| 亚洲欧美综合区自拍另类| 国产特级全黄一级毛片不卡| 久久精品国产亚洲av高清蜜臀| 日本熟女人妻一区二区| 日韩av一区二区三区高清| 久久性爱视频| 真人二十三式性视频(动)| 高潮社区51视频在线观看| 国产av丝袜熟女丰满一区二区| 小辣椒福利视频导航| 精品人妻少妇一区二区不卡| 国产精品一区二区av白丝在线| 极品少妇一区二区三区四区视频| 放荡的美妇在线播放| 国产精品天天在线午夜更新| 日本色偷偷| 乳乱中文字幕熟女熟妇| 人人人妻人人澡人人爽欧美一区 | 亚州五十路伊人网| 日产一区日产2区日产| 国产aⅴ无码专区亚洲av麻豆| 久久久伊人影院| 日韩精品成人一区二区三区| 亚洲熟女精品中文字幕| 躁躁躁日日躁| 99久久久精品国产性黑人| 亚洲熟女天堂av一区二区三区| 国产免费又爽又色又粗视频| 精品国产一区二区三区av片| 国产精品白浆一区二区免费看 | 自拍偷自拍亚洲一区二区| 天美传媒一区二区| 国产一区二区三区韩国|