1、 A Conditional sentences We have already learnt to use conditional sentences to talk about probable results We can also use conditional sentences to talk about results that will certainly happen.The if-clause talks about a possible action If you put salt into water,it disappears.The main clause talk
2、s about the result that will certainly happen Work out the rule When we use a conditional sentence to talk about something that will certainly happen,both verbs should be in the simple present tense/the simple future tense.Things to remember We can also put the if-clause after the main clause.Salt d
3、isappears if you put it into water.A1 Read these if clauses and draw lines to match them with the results1.If you take a fish out of water,a it grows 2.If you switch off the lamp,b it dies3.If you put wood into water,c the room becomes dark4.If you water a plant,d it breaks5.If you drop a galss,e it
4、 floats A2 In pairs,make conversations about the sentences in A1 on page 103.Following the example.S1:What happens if you take a fish out of water?S2:It dies.S1:Are you sure?S2:Of course.I am sure.If you take a fish out of water,it dies.A3.Complete these sentenses with the words in brackets.1 If you
5、 _ice,_ water.(turns/heat/it/into)heatit turns into 2.If you _steam,it _water.(into/cool/turns/it)3.Oil _water.(on/floats/pour/if/you/if)4.Water _it(you/heat/boils/if)coolit turns intofloats if you pour it on boils if you heat B ifnot and unless The word unless can mean if not.For example,the two se
6、ntences below have the same meaning:If you do not get enough sleep every night,you will not remember things well.Unless you get enough sleep every night,you will not remember things well.Things to remember We can also put the if clause and the unless clause after the main clause.You will be late for
7、 school if you do not leave now.unless you leave now.B1 Draw lines to match the beginnings of the sentences in Column A with the endings in Column B.1 We will have a picnic tomorrow a you will not play it well 2 I will finish the book todayb if it does not rain 3 Unless you want to watch something c
8、 I will switch the television off now4 I am going to buy a dress for my mother.d unless I can think of a better idea for a present5 Unless you practise playing the piano every day.e unless I feel tired B2 Rewrite the following sentences with unless.1 If you do not improve your handwriting,you will l
9、ose marks in the exam.Unless you improve your handwriting,you will lose marks in the exam.You will lose marks in the exam unless you improve your handwriting.2 You will get a toothache if you do not brush your teeth every day.You will get a toothache unless you brush your teeth every day.Unless you
10、brush your teeth every day,you will get a toothache.3.This room will get very hot if you do not open the window.This room will get very hot unless you open the window.Unless you open the window,this room will get very hot.4 If you do not close that window,flies will get in.Unless you close that window,flies will get in.Flies will get in,unless you close that window.5.I will leave this restaurant if the waiter does not come soon.I will leave this restaurant unless the waiter come soon.Unless the waiter come soon,I will leave this reataurant.Thank you!