Suggested answers:

　　1.a　2.b and c　3.d　4.e　5.c and e,because you can easily find the subject of the active voice after "by".

　　T:From the sentences above,we can know the structure of the passive voice:be+done.Tenses are observed through the "be" verb.So the structure of the passive voice in the present,the past,the future,and the present perfect forms are as follows:am/is/are+p.p.(the present simple);was/were+p.p.(the past simple);will be+p.p.(the future simple);and have/has been+p.p.(the present perfect form).Now please make the sentences in Activity 2 using the correct tense of the passive voice.

　　Example:These shoes/make/in Italy

　　These shoes are made in Italy.

　　1.These computers/produce/in America

　　2.Rice/grow/in China/for/thousands of years

　　3.These electronic games/make/in Japan

　　4.A new variety of rice/discover/in 1970

5.Many important discoveries/make/since/the beginning of last century 　　Ask the students to complete their answers individually,then check with a partner.Ask some of them to report their answers.

　　Suggested answers:

　　1.These computers are produced in America.

　　2.Rice has been grown in China for thousands of years.

　　3.These electronic games are made in Japan.(could also be "were made")

　　4.A new variety of rice was discovered in 1970.

　　5.Many important discoveries have been made since the beginning of last century.

　　After the students finish sentences,ask the whole class to answer the additional activity:what form of the passive voice are the sentences?

　　Suggested answers:

　　1.present simple　2.present perfect　3.present simple(past simple)　4.past simple　5.present perfect

　　T:Now class,I think you have mastered the use of the passive voice.Let's do another two activities to consolidate what we've learned.First,complete the sentences using the verbs in brackets in Activity 3.Ask the students to fill in the blanks individually,then the teacher let some volunteers speak out their answers.During class,the teacher should encourage the students to be active in class,and give the students more chances.(Show the following sentences on the screen.)

　　1.As a boy he __________(educate)in many schools.

　　2.He __________(give)the nickname,"the student who asks questions".

　　3.The results of his experiments __________(publish)in China in 1966.

　　4.Finally,in 1970 a naturally sterile make rice plant __________(discover).

　　5.50 thousand square kilometers of rice fields __________(convert)to growing vegetables.

6.Following this,Yuan Longping's rice __________(export)to other countries. 　　Suggested answers:

　　1.was educated　2.was given　3.were published

　　4.was discovered　5.were converted　6.was exported

T:Just now,you've got the whole sentences correctly.Now let's do a further job.Write