您正在看的高中一年级是:人教版高一Unit 19　Modern agriculture。 emphasize almost any part of the sentence (except emphasizing the verb).Besides,if we emphasize the subject,“who”(referring to a person)is possible instead of “that”.If an object is emphasized,“whom”(referring to a person)is possible.Look at the screen.Read this sentences and rewrite them,emphasizing the parts underlined,using“It is/was…that…”.Please prepare them in pairs.

　　Rewrite the sentences:

　　1. The children often help the father and mother do the farm work.

　　2. In 1993,a tomato was developed that was very different from any grown before.

　　3.The biggest problem of Chinese farmers is the shortage of arable land.

　　4. The plants grown in greenhouses are protected from the wind,rain and insects.

　　5.Future agriculture should depend on high technology as well as traditional methods.

　　(After a few minutes.)

　　T:Are you ready?(Ss:Yes.)Please change these sentences.One student,one sentence.Who will be the first?

　　Sb:I'll try.Sentence 2:It is the children who/that often help the father and mother do the farm work.

　　Sc:I want to rewrite the second sentence,but I'm not sure whether I should use“is”or“was”.

　　T:Here you should use “was”.

　　Sc:Sentence I:It was in 1993 when a tomato was developed that was very different from any grown before.

　　T:Is he right,Sd?

　　Sd:Yes.

　　T:You're both wrong.We should pay special attention to “that”when we emphasize the adverbial of time and place.In both situations,we should use“that”instead of “when ”or“where”.Are you clear about that?

　　Ss:Yes.

　　T:Let's go on with the other sentences.

　　Se:Sentence 3:It is the shortage of arable land that the biggest problem of Chinese farmers is.

　　SF:Sentence 4:It is the plants grown in green houses that are protected from the wind,rain and insects.

　　SG:Sentence 5:It is high technology as well as traditional methods that future agriculture should depend on.

　　T:Are they right?

　　Ss:Yes,they are all right.

　　Step Ⅳ.Practice

　　T:Now let's do the second part of Grammar.Rewrite the sentences,emphasizing as many parts as possible.First look at Example.Read it carefully and then do the exercise.You can have a discussion with your classmates if you have any questions.A few minutes later,we'll check the answers.

　　(When students finish,teacher shows the answers on the screen and get the students to check their answers.Then teacher answers the questions raised by the students.)

　　Answers to the exercise:

　　1.It was Herry who/that gave George a new tie for his birthday last year.

　　It was George whom/that Herry gave a new tie for his birthday last year.

　　It was a new tie that Herry gave George for his birthday last year.

　　It was last year that Herry gave George a new tie for his birthday.

　　2.It was during that period of time that they made three important discoveries.

　　It was they who/that made three important discoveries during that period of time.

　　It was three important discoveries that during that period of time they made.

　　3.It is some people in South America who /that still practise this kind of farming.

　　It is this kind of farming that some people in South America still practise.

　　Step Ⅴ.Summary and Homework

　　T:In this class,we've done some exercises about Word Formation.Please remember these words on the blackboard(Pointing to the blackboard).We should also remember the emphatic construction:It is …that(who,whom)…What should we pay special attention to?Who can tell us?

　　Sh:1.The verb can not be emphasized.

　　2.When we emphasize the adverbial,we should remember that we cant't use when or where.

　　T:(Write what the student said on the blackboard.)That's right.After class,we should do more exercises so that we can master it.Today's homework:Do the exercises concerned in the workbook.That's all.Class is over.

　　Step Ⅵ.The Design of the Writing on the Blackboard.

　　Unit 19　Modern agriculture