111Unit 21 Lesson 1 Chewing gumWarm-upTeaching aims1.    new words and phrases2.     warm-up3.     study the text: To chew or not to chew4.     grammar: conditionalsTeaching time Two periodsTeaching processStep 1 Revision:1.    have a dictation (unit 20 new words)2.    check homework exercisesStep 2 new words learning1.ask some students to read the new words first and correct their pronunciation2.play the tape and have them read after the tape3.give them a few minutes to read the new words freely ,tell them if they cant read the new words, encourage them to ask the teacher .Step 3 Warm-up1.Read unit objectives, and ask the students to tell us the meanings.2.warm-up :Exercise 1 a)ask students read the key words first, then guess their meanings, have them translate the key words into Chinese. b)students work individually, matching six of the key words with the numbers in the picture.Then, check their answers. c)ask them read the key words.3.Exercise 2a)     listen to the tape twice, have students guess which part of the body are being described.b)     play the cassette ,pausing after each section to check their answers. C )answers:1.brain 2.heart 3.hungs 4.eye 5.liver4.Exercise 3 a)make sure the class know what to do. Then play the tape twice, ask some students to say their answers to the class.5.Exercise 4:work in pairs and test your body “machine” a)read out the instructions to the class and check that students understand them. b)have the students work in pairs and discuss the questions.6.exercise 4:give students a few minutes to do the questionnaire in pairs. Then check their scores on page 103.step 4 Reading1.Before you start a) read the exercise 1 and give them a few minutes to discuss the questions b)ask some students to share their ideas with the class.2.Read to learna)     ask the students look at exercise 2 and 3, and then play the cassette twice.b)     give them ten minutes to read the text and complete the table.c)     check theirs answers3.exercise 4a)     give students some time to do the exercises in pairsb)     ask some students to answer the questions4.Language pointsa)Diet specialists regularly inform us that it is important to chew our food properly. 營(yíng)養(yǎng)學(xué)家們經(jīng)常告誡我們一定要正確咀嚼食物。 句型:It is +adj.+to do sth. It是形式主語(yǔ),動(dòng)詞不定式是真正的主語(yǔ). b)it will help our bodies digest it better.這樣才能有助于身體更好地消化食物.help sb.do sth.c)     does chewing gum have any effect on this process?咀嚼口香糖對(duì)這一過(guò)程有什么影響呢?Have any effect on d)     one obvious benefit of chewing gum is that it fights bad breath.一個(gè)顯而易見的好處是嚼口香糖能清除口腔異味. That 引導(dǎo)的是表語(yǔ)從句.Bad breath口腔異味e)     if it has green plants materials added to it.have sth. done.Add tof)     tooth decay 蛀牙 g)wash away清除 h)lose weight減肥 i)carry out進(jìn)行,執(zhí)行,開展 j)up to 一直到,等于 k)by now到如今 l)today, there are gum products that help smokers give up their bad habit.That引導(dǎo)的定語(yǔ)從句修飾gum products,在從句中做主語(yǔ). Give up放棄 m)the negative side of n)the production of stomach acid and digestive juices o)it has also been proven that chewing gum for long periods of time means that the body does not have time to rest.p)lead to q)someothers. r)send out v.發(fā)送, 派遣, 放出 s)instead of t)brush ones teethu)the number of 的數(shù)目；數(shù)量v)on balance adv.總而言之step 5 grammar: conditionals revision1.exercise 6-9read the instructions to the class. give them some time to do the exercises individually.Then ask some students come to the blackboard to do them.Step 6 Summary and homeworka)     summary b)homework: new words and do exercises on page 80-81111