Unit 19　Modern agriculture

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
the third period
word formation:
verb          noun
irrigate          irrigation
moderniz         emodernization
populate          population
produce          production