111Unit21 Human BiologyTeaching aims1.words and phrases2.to write a discursive essay3.to practise using linking words and phrases4.to listen to and understand a TV panel discussion5.to finish the exercises about the text6.pronunciationTeaching time Two periodsTeaching processStep 1 Revision1.dictation2.check the 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 tape.Step 3 writing1.exercise 1a)ask students to read the given words and expressions in exercise 1 first .b)read the instructions and the example sentence to the class.c)ask some students do exercise 1 on blackboard2.exercise 2a)give students a few minutes to read the text and do the exerciseb)check their answers3.exercise 3a)students do the exercise individuallyb)check their answers by having individuals read out the sentences.step 4 listening:a TV programme1.exercise 1a)read out the types of programme to the class.make sure that they understand what they are.b)look at the picture,let students guess what type of programme this is.2.exercise 2a)listen to the cassette for students to check their answer to exercise 1.b)play the tape again,let students put these topics in the order they are mentioned.3.exercise 3a)let students read the sentences firstb)play the cassette twice for them to complete the sentence.c)check their answersstep 5 pronunciation:exercise 41.give students a few minutes to read through the sentences and the option answers2.play the tape twice for students to listen and choose the correct meaning.3.check the answersstep 6 speaking:a discussion1.exercise 1,read out the instructions to the class first. then play the cassette twice for students to decide what Toms and Jans opinions are.2.exercise 2a)let students read through the words and colloquial expressions.b)play the tape twice for students to match the words and expressions3.exercise 3,students do the exercise in pairs, then check their answers.step 7 homeworkexercise 2 on page 87 111