Grammar (8).ppt

1、九年级上册,英语教学课件系列,Unit 6 TV programmes Grammar,To learn to use if and unless,A Using if,We use if to talk about the result of a possible action. We make sentences with if like this：,We put a comma after the if-clause when it is the first part of a sentence.,Tip,if引导的条件状语从句,由引导词if或unless引导的状语从句叫做条件状语从句。

2、 状语从句中的动作实现后，主句中的动作才能发生,Summary,if引导的条件状语从句可以位于主句之前，也可位子主句之后。如果从句在前，从句 与主句之间要用逗兮隔开。 If you fail in the exam, you will let him down. 如果你考试不及格，你会让他失望的。 You will get good grades if you study hard. 如果你努力学习，就会取得好成绩。,在if引导的条件状语从句中，主句中的动词常用一般将来时，从句中的动词用一般现在时，即“主将从现”原则。 If you ask him, he will help you. 如果你

3、请他（帮忙），他会帮你的。 They are going to have a picnic if they are free next Saturday. 如果下周六有空，他们就去野餐。,在if引导的条件状语从句中，主句也可含有情态动词或是祈使句。 If it is fine tomorrow, we can go and fly the kite. 如果明天天气好，我们可以去放风筝。 Dont miss the programme if you like music. 如果你喜欢音乐，不要错过这个节目。,注意: 在if引导的条件状语从句中，无论主句用一般将来时、情态动词还是祈使句,从句均 用

4、一般现在时。,变换：含有if引导的条件状语从句的复合句中，当主句主语和从句主语均为you时，可转换为“祈使句，and + 简单句”或“祈使句，or + 简单句”。,You can get good grades if you work hard.,= Work hard, and you will get good grades,If you dont get up early, you will be late again.,= Get up early , or you will be late again.,What will happen if? A1 Millie is thinki

5、ng about herself, her friends and TV programmes. Help her choose the correct forms of the verbs in brackets to complete the sentences. If I (go, will go) to the Reading Club this afternoon, I (do not have, may not have) any time to watch TV.,2. If Simon (gets, will get) home too late, he (misses, wi

6、ll miss) his favourite cartoon. 3. If Amy (completes, will complete) all her homework quickly, she (watches, will watch) the chat show. 4. If Daniel (takes, will take) part in the game show, he (wins, might win) a prize. 5. If Sandy (finds, will find) a programme interesting, she (introduces, will i

7、ntroduce) it to us.,Work out the rule!,We often use the simple _ (future, present) tense in the if-clause. We need a _ (comma, full stop) after the if-clause when it is the first part of a sentence.,present,comma,Asking about animals A2 Millie watched a documentary about animals. Help Millie answer

8、her fathers questions with the help of the words in the box.,is in danger,Dad: What will a bear do if its in danger? Millie: If a bear _, it (2)_ _ people.,attack catch hunt live protect walk,will,attack,Dad: What will a polar bear do if its hungry? Millie: If a polar bear (3)_, it (4)_fish from the

9、 water. Dad: What will elephants do if theyre thirsty? Millie: If elephants (5)_, they (6)_until they find a river. Dad: What will tigers do if they live in the wild?,is hungry,will catch,are thirsty,will walk,Millie: Tigers (7)_for their own food if they (8)_. Dad: What will tigers do if they have

10、babies? Millie: Tigers (9)_ as a family if they (10)_. Dad: What will male wolves do if theres danger? Millie: Male wolves (11)_their families if there (12)_.,will hunt,live in the wild,will live,have babies,will protect,is danger,B Using unless,We can use unless to say that something can only happe

11、n or be true in a particular situation. The situation will continue unless humans stop hunting them for their fur and bones.,Sometimes we can use if . not to replace unless. The situation will continue unless humans stop hunting them for their fur and bones. The situation will continue if humans do

12、not stop hunting them for their fur and bones. Unless it rains tomorrow, we are going to play football in the park. If it does not rain tomorrow, we are going to play football in the park.,The unless-clause can come first or after the main clause. Unless you try your best, you will not realize your

13、dream. You will be late unless you leave right now.,unless引导的条件状语从句,Summary,unless引导条件状语从句： Unless he studies hard, he will never pass the exam. 除非他刻苦学习，否则考试永远不能及格。 We will not get there on time unless we leave earlier. 如果我们不早点离开，就不能准时到那里。,unless意思足“除非，如果不”，相当于ifnot。如： You will be late unless you le

14、ave at once. 如果你不马上走，你将会迟到。 =If you do not leave at once, you will be late. Shewillkeeponsingingunlesssheis toldtostop. 她会一直唱下去，除非有人叫她停止。 =shewillkeeponsingingifsheisnot toldtostop,也可以用or“否则”来做同义句转换 Unlessyoulistencarefully,youwont knowtheanswer. 除非你认真听讲，否则你就不知道答案。 =Ifyoudontlistencarefully,youwont

15、knowtheanswer. =Youshouldlistencarefully,oryou wontknowtheanswer.,注意:当某种条件所引起的结果是一种情绪或想法时，不能使用unless,只能用ifnot。如: I will be angry if I am not invited to the party. () I will be angry unless I am invited to the party. (),在unless引导的条件状语从句中，主句中的动词常用一般将来时，从句中的动词用一般现在时。即“主将从现”如: Unless it rains, the game

16、will be played.除非下雨，否则比赛将照常进行。,同if引导的条件状语从句一样，在unless引导的条件状语从句中，主句也可以含有情态动词 或是祈使句。如： He cannot see clearly unless he wears glasses. 他不戴眼镜就看不清楚。 Dont touch the machine unless the teacher allows you to. 没有老师的允许，不要乱动机器。,Sandy has prepared some tips for a school trip to a film and TV studio. However, sh

17、e tore the tips by accident. Help her put the tips back together. Match the two parts of the sentences and write the correct letters in the blanks.,A trip to a film and TV studio,1. Unless the weather report says it is going to rain, _ 2. We will arrive at the studio around 9:30 a.m. , _ 3. Unless y

18、ou already know the studio my very well, _ 4. You will buy your lunch at the restaurants in the studio, _ 5. Unless you arc tired, _ 6. You will have a chance to see how a TV programme is recorded, _,c,d,f,a,b,e,unless you take your own food with you. you will not need to take the minibus in the stu

19、dio. you will not have to take an umbrella with you. unless the traffic is very heavy. unless you have little interest in it. you travel around it with a tour guide.,Work out the rule!,We use the simple _ (future, present) tense in the unless-clause.,present,Exercises,1.IfI_hisphonenumber,Iwilltell

20、you. A.find B.found C.willfindD.havefound 2.Wewillgocampingifit_tomorrow. A.Wontrain B.didntrain C.doesntrainD.isntraining,A,C,一单项选择题。,3.Imwaitingformyfriend.Ifhe_, I_swimmingalone. A.doesntcome;willgo B.wontcome;willgo C. willcome;wontgo D.dontcome;willgo 4._yougotothesupermarketat 7p.m.,youcanbuya

21、lotofcheap food. A.If B.Unless C.WhetherD.When,A,A,5.Iwontgettothepartyontime_ I catchthefirsttraintomorrow morning. A.if B.unless C.whetherD.when 6.Shallwegoonapicnicthisweekend? Goodidea!Unlessit_. A.rains B.doesntrain C.rain D.wontrain,B,B,7. CanIchangethejacketforanother one_itdoesntfitmewell? -Ofcourse. A.unless B.if C.that D.though 8.Nobodycanlearnmathswell_he workshardonit. A.if B.unless C.thought D.however,B,B,9.Iffish _ awayfromwater, they _ die. A.aretaking,wontB.aretaken,will C.arebeingtaken,willD.take,wont 10.Eachstudentcanaskteachersfor hel