教學目標
1. 圍繞“禁止和警告”，學習應遵守交通規則的交通用語。排隊看病，告訴人們應遵守公共秩序。家庭集會不要時間太久、太吵。
2. 學習情態動詞must的用法。
3. 學習when, before, after等引導的時間狀語從句，及if引導的條件狀語從句。
重點難點
1. if引導的條件狀語從句
(1)條件狀語從句在復合句中作主句的條件狀語。
(2)這種句子，如果主句是一般將來時，或者是含情態動詞must, can, may的謂語動詞時，從句則用一般現在時，如：
I won't go by plane if it rains tomorrow. 如果明天下雨我就不坐飛機去。
If you get up late, you'll be late for school. 如果起床晚了，你就要上學遲到。
You can pass the exam if you study hard. 假若你努力學習，你就能考試及格。
If you don't hurry, you will miss the train. 如果不快點，你 就趕不上火車了。
2. 時間狀語從句
連詞when, before, after引導的時間狀語從句，要特別注意當主語是將來時時，從句要用一般現在時；主句的謂語動詞是情態動詞+動詞，從句的謂語，用一般現在時；主句是祈使句時，從句也要用一般現在時。主句用過去時，從句也要用過去時態，從句可以放在主句之前，也可放在主句之后。如放在主句之前，從句用逗號與主句隔開。
When the lights are red, the traffic must stop.
He liked reading when he was young.
Please don't go to bed before your mother comes back.
3. You mustn't eat anything until you see the doctor.
直到你看了病才能吃東西。
until “直到…為止”，可作介詞，也可作連詞
(1)until 作介詞時，后跟名詞或相當于名詞的詞或短語。例如：My father worked until twelve at night. 我父親一直工作到晚上十二點。
I didn't get up until ten in the morning last Sunday. 上星期日直到上午十點我才起床。
(2)作連詞，引導一個時間狀語從句，常用于“not…until”“直到…才”結構，此時，主句的動詞是終止性的或稱瞬間動詞，比如：go, come, move, leave等。此時，翻譯時要先譯until 引導的句子和詞組。如：
They won't go to bed until their mother comes back.
直到他們的媽媽回來了他們才去睡。
I didn't leave until he finished having breakfast.
直到他吃完了早飯我才走。
當主句是肯定形式，主句謂語動詞是延續性的，翻譯時英、漢語序相同。如：
I waited until he came. 我一直等到他來。
He'll sit here until 9 o'clock. 他將坐到九點鐘。
(3)not…until 與 not…before的異同。
He didn't go to bed until he finished his homework. 這句話也可表達為：He didn't go to bed before he finished his homework.
但并不是任何情況下都可互換，在有具體的時間時，有區別。
如：He didn't go to bed until 11 o'clock. 他直到11點才去睡。
而He didn't go to bed before 11 o'clock. 表示他可能在十一點前，也可能在十一點以后睡覺。
4. 情態動詞must的用法
must: 沒有人稱和數的變化，需和動詞原形連用。
(1)表示必要，必須。
You must be careful!
We must study hard.
(2)表示推測，可能性很大，“一定”“必定”的意思。
She must be our new English teacher.
Mr. Wang must be at work. 王先生想必在工作。
(3)mustn't 表示“禁止”，絕對不許做(某事)。加強語氣時用must never.
You must not play football on the road.
You must never talk to your father like that.
(4)回答 must 開頭的問句時，肯定式用must, 否定式用needn't，不用 mustn't。
Must we do homework every day? Yes, you must. /No. you needn't.
知識總結
1. 掌握本單元單詞積累部分詞匯及詞組。
2. 掌握must的用法。
3. 掌握when, before, after引導的時間狀語從句及if引導的條件狀語從句，特別是時態，主句和從句要一致。
核心知識
常用單詞
alone, arrive, bell, care, change, complain, disturb, fact, half-way, head, hit, hurt, jumper, knee, live, mistake, necessary, noise, passenger, patient, plastic, police, push, quarrel, queue, quiet, quietly, surprise, telephone, themselves , turn, visitor, voice
at midnight 在半夜(子夜) enjoy oneself 過得快樂，玩得痛快 get off 下來，從…下來 get on 上(車)，have a good time 過得快樂， in fact 實際上，實事上 laugh at 嘲 笑， make a noise 吵鬧，quarrel with sb 與某人吵架，stand in (the) line 站在隊里 ， throw about 亂丟、拋散 waiting room 候診室 catch a bus 趕車 be careful 當心， 小心 have an accident 出事故 wait in line 排隊等候 wait for one's turn 等候輪到 某人，按次序等候 at a bus stop 在車站， a queue jumper 不排隊等候的人，插隊者 be in the queue 排隊，站隊 see a doctor 看病 take one's arm 拉某人的胳膊 get ready for 為…作準備 not…until… 直到…才… a plastic bag 塑料袋 complain about sb/s th 對某事不滿，抱怨某事，抗議某事 in a tired voice 用疲倦的聲音 at the head of 在…前面
基礎知識
1. You must be more careful!你一定要更加小心!
careful 的比較級是 more careful
be careful “小心，當心”其同義詞是look out, take care
Be careful not to play football in the street. 注意不要在街上踢球。
Take care when you cross the road. 過馬路時要小心點。
Look out! The bus is coming!當心!車來了。
2. That car nearly hit you. 車幾乎撞上你了。
nearly 副詞、作狀語，修飾動詞 hit， 意思是“幾乎，差不多”一般放在行為動詞前，be 動詞后，一般不修飾表否定意義的詞。
如：I am nearly thirty. 我差不多三十歲了。
We are nearly ready for travel. 我們差不多為旅行作好了準備。
The old man nearly died. 那位老人幾乎死了。
3. When you get on the bus, you mustn't push others.
當你上車時，你一定不要推別人。
get on“上(車)”，反義詞 get off “下來，從…下來”
push“推” 反義詞是 pull “拉、拖”
4. You must stand in the line and wait for your turn.
你應該排隊按次序等候。
(1)stand in line “排隊”近義詞是wait in a queue 排隊等候
注意下面說法：jump the queue 插隊
wait in line=wait in a queue 排隊等候
be in (the) line. 在隊列里，排隊=be in the queue
a queue jumper 插隊的人。
(3)wait for one's turn 等著輪到某人，按順序等候
如：Don't jump the queue. Wait for your turn, please.
不要插隊，請按順序等候
turn 這處是作名詞，“順序、次序”。句型：
It's one's turn to do sth. 輪到某人做某事
如：It's my turn to clean the blackboard. 輪到我擦黑板了。
It's Li Lei's turn to be on duty. 輪到李磊值日了。
5. It is better to wait and be safe. 最好等到安全。
It 在這句中是形式主語，to wait and be safe 是動詞不定式作真正的主語。當不定式作 主語時，常常用it作形式主語，而將不定式放在句末，試比較：
To study English is not easy.
It is not easy to study English. 學習英語 不容易。
To climb that tree is dangerous.
It is dangerous to climb that tree. 爬那棵樹危險。
It's bad for you to read in bed. 躺在床上看書對你有害。
To read in bed is bad for you.
6. The people are waiting for the doctor to come. 人們在等醫生來。
“to come” 是動詞不定式作賓語補足語，補充賓語“the doctor”。例如：
I invited Tom to have dinner with me this Sunday.
這個星期天我邀請湯姆同我吃晚餐。
I wanted him to wait for me after school.
我想要他放學后等等我。
We are waiting for the rain to stop. 我們正等著雨停下來。
The farmers waited for spring to come. 農民們期待著春天到來。
7. At the head of the queue was an old woman. 排在隊伍前頭的是一位老太太。
(1)at the head of 意為“在…前頭”、“居首位”，反義詞是at the end of “在…末尾 ”，如：
My father always sat at the head of the table. 我父親總坐在桌子的上首。
I put my address at the head of the letter. 我把我的地址寫在信的上方。
Li Ming is at the head of his class. 李明是班上第一名。
(2)本句是倒裝句。在英語中，當表示地點、方位的介詞短語放在句首時，句子常要倒裝， 即將連系動詞或謂語動詞提到主語前面，(謂語常為不及物動詞)：
On the left side of the river were rows of fruit trees. 河的左岸是一排排果樹。
In front of the house stands a big tree. 房子的前面有一棵大樹。
Behind the factory is a hospital. 工廠后面是一家醫院。
Among the children sat an old man. 在孩子們中間坐著一個老人。
8. She wanted to see the doctor because her back hurt. 她要看病，因為她的背痛。
此處hurt是不及物動詞，意為“痛”，如：
My feet hurt. 我的腳痛。
Does your leg still hurt? 你的腿還痛嗎?
hurt 也可作及物動詞用，表示“使…受傷”，如：
He hurt his back when he fell. 他摔倒時背部受了傷。
The boy hurt himself. 那孩子受傷了。
9. She sat nearest to the doctor's door. 她坐在離醫生的門最近的地方。
(1)nearest 在這里是副詞，near的最高級，副詞最高級前可省去the, 如：
He studies hardest of all. 在所有的人中，他學習最努力。
They all came early but she came earliest. 他們都來得早，而她來得最早。
(2)near to, next to 都作“鄰近”解，是far from的反義詞，如：
He lives near to the post office. 他住在靠近郵局的地方。
I live nearer to the post office than you. 我住的地方比你住的更靠近郵局。
He lives next to me. 他住在我的隔壁。
The post office if next to the school. 郵電局就在學校隔壁。
She sat next to her mother. 她坐在她媽媽身旁。
10. She lives in the country. 她住在鄉下。
in the country “在農村，在鄉下”，對應詞是in the city. “在城市”。
country 一詞除指“國家”外，還有“農村、鄉下”的意思，用時一般要加定冠詞the(=the countryside)。例如：
be/come from the country 來自農村
live/work in the country 在農村生活(工作)
country 還可為形容詞，作定語。例如：
a country girl 鄉下姑娘； country life 鄉村生活； country roads 鄉間道路
I was born in the country but my younger sister was born in the city.
我出生在農村，但我的妹妹生在城里。
11. She stood up and took his arm. 她站起來，抓住他的手臂。
take sb's arm 意思是“抓住某人的手臂”。類似的用法有take sb's hand(s)，意思是“ 握住某人的手(雙手)”。
12. Everyone laughed at the woman's mistake. 人人都為那婦女的錯誤而發笑。
laugh at 有“因……而發笑”或“嘲笑”的意思。再如：
Don't laugh at her. 不要嘲笑她。
They all laughed at my story. 他們聽了我的故事都笑了。
Why do you laugh at this idea? 你為什么覺得這個想法好笑?
13. Why are you in bed? 你為什么還在床上?
in bed 有“睡覺”、“在床上”、“臥床”等意思，用時一般加“be”。再如：
Granny Li is still in bed. 李奶奶仍在臥床。
He is in bed with a cold. 他感冒躺下了。
14. I feel a little better now. 我現在感覺好一點。
a little 可用來修飾比較級，表示程度。
He is a little taller than I. 他比我高一點。
My desk is a little better than his.
我的課桌比他的好一點。
15. If you are ill, you'll have to see the doctor.
如果你病了，你得看病。
(1)be ill= be sick “生病”ill在系動詞后，作表語。類似用法有：be quiet 安靜，feel well 感覺舒服，be late 遲到， be alone 單獨的，寂寞的。
(2)see a doctor “看病，看醫生”
16. You mustn't throw them about. 你一定不要亂丟它們。
throw about “亂丟、拋散”。about 在此是副詞，當賓語是名詞時，可放在about前面和后面。賓語是代詞時，只能放在throw about的中間。如：
Don't throw the waste paper about=Don't throw about the waste paper. 別把廢紙到處丟。
These are your books. Don't throw them about. 別亂丟。
17. When my mother reached home. 當我媽媽到家時。
People in the USA can't drink beer or wine before they reach 21.
美國人在年齡到了21歲才能喝啤酒或白酒。
reach 及物動詞，“到達”同義詞是get和arrive，這兩個詞是不及物動詞，后接地點名詞時，要加介詞，分別是get to 和arrive at(in). 大地點用in,
如：Last year they reached China=Last year they got to China=Last year they arrived in China.
18. Their friends enjoyed themselves at the party.
在晚會上他們的朋友玩的很愉快。
enjoy 后接反身代詞，構成短語 enjoy oneself “過得快樂，玩的痛快，”=have a good time, enjoy 后有動詞時，動詞要加ing。
如：I enjoyed myself in the park last Sunday. 上周日我在公園玩的痛快。
He enjoyed himself on his birthday. 他生日過的快樂。
19. You must stop making so much noise. 你們必須停止吵鬧。
(1)stop doing sth 停止做某事。
stop to do sth 停下來做某事。(指停下正做的事，來干另一件事)
如：He stopped to talk with me. 他停下來同我交談。
When he saw our teacher coming, he stopped talking with me.
他看到老師來了，就停止同我談話了。
(2)make a noise 吵鬧 make much noise 太吵鬧，發出大聲，noise可作可數名詞，也可作不可數名詞。
典型例題
【課本難題解答】
1. If it rains tomorrow, we to visit the Museum.
A. don't go B. won't go C. aren't go D. didn't go
解析：在條件狀語從句中，用一般現在時，而主句用一般將來時。故選B對。
2. After he heard the news, he me soon.
A. calls B. will call C. called D. is calling
解析：在含有時間狀語從句的復合句中，主句和從句的時態要一致。從句用過去時，主句也 用過去時，故選C對。
3. An old grandpa is standing in the head of the queue. (找出錯項并改正)
A B C D
解析：at the head of “在…前頭”是固定搭配，故C錯，in應改成at.
4. 直到我親眼看到了，我才會相信這件事。
A. I won't believe it until I see it with my own eyes.
B. I believe it until I see it with my own eyes.
C. I didn't believe it until I see it with my own eyes.
解析：(1)not…until 是“直到…才…”的意思。(2)主句和until引導的時間狀語的時態要保持一致。B句不是not…until. C句時態不一致，故選A對。
【關于“Unit 17 You must be more careful”的常見問題】
常見問題1: Unit 17 You must be more careful
問題：
讀懂下文，并選擇填空。
December 1 is Christmas Day. Christmas is an important(重要的) holiday 2 the United 3 . 4 this day, most families get together 5 a big dinner. They exchange(交換) presents and visit friends. The Christmas tree is an important 6 of the Christmas holiday. Most families buy a tree. The family decorate(裝飾) the tree 7 .
Santa Claus(圣誕老人) has a white beard(胡子) and 8 a red suit(衣服 ). Parents always 9 their children that Santa Claus brings presents to all good children. He travels in a sleigh(雪橇) and comes down the chimney( 煙囪). He 10 the presents under the Christmas tree.
1. A. twenty five B. 25th C. 26th D. twenty and five
2. A. at B. on C. in D. to
3. A. State B. Nation C. States D. Country
4. A. In B. At C. Into D. On
5. A. for B. with C. in D. over
6. A. parts B. part C. party D. the part
7. A. alone B. everyone C. together D. both
8. A. put on B. wears C. put in D. wear
9. A. tell B. told C. tells D. say
10. A. puts B. put C. putting D. to put
解答:
分析：1. B。12月25日是圣誕節 2. C。在某國用介詞in 3. C。用復數 4. D。在具體某一天用介詞on 5. A。for表示目的或原因 6. B 7. C 8. B。wear表示穿的狀態。用一般現在時與上句謂語一致 9. A 10. A。用puts與整篇時態一致。
常見問題2: Unit 17 You must be more careful
問題：
不變原意改寫句子。(山西 2000)
1. Uncle Wang is on a visit to Japan.
Uncle Wang Japan.
2. We were all here before you.
We all here you.
3. You must be careful. That car nearly hit you.
You must . That car nearly hit you.
4. You must always wait in a line.
You must always wait .
5. It's very nice talking to you.
It's very you.
6. Why don't you come and play basketball?
and playing basketball?
7. It's so hot that I can't wear the coat.
It's to the coat.
8. You mustn't eat anything until you see the doctor.
anything you see the doctor.
解答:
1. is visiting 2. came, earlier, than 3. take care 4. for your turn 5. nice to talk to 6. What about coming 7. too hot, wear 8. Don't eat, until
常見問題3: Unit 17 You must be more careful
問題：
單元寫作書面表達：根據圖畫提示完成下列對話。
①Bill 說，瞧多高的一棵樹啊!Jack說他要爬那棵樹，他擅長爬樹。Bill說，小心，很危險的。Jack說不危險他可從樹上把花摘下來。Bill 勸告他，千萬別干，樹太高了，Jack不聽，他說很容易的。結果從樹上摔了下來。
②用上這些提示詞：climb up, be good at, be careful， look out，dangerous， pick ， flowers， easy.
Bill: Look, What a tall tree.
Jack: 1 . 2 . Let me show you.
Bill: 3 , Jack. It's dangerous.
Jack: No, 4 . It's quite safe. 5 .
Bill: You mustn't do it, Jack. 6 .
Jack: It's 7 . I can do it. Watch!
Bill: 8 !
Jack: Ouch!(He falls off the tree)
解答:
1. I'll climb up the tree. 2. I'm good at climbing trees. 3. Be careful. 4. It's not dangerous. 5. I can pick some flowers from the tree. 6. It's too high . 7. easy 8. Look out.