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　　unit3 amazing people-grammar and usage学案
　　Teaching aim:
　　To give a brief introduction to the present perfect tense
　　Teaching procedures:
　　1 Go over the news story on Page 2 and find the sentences using the present perfect tense.
　　Please explain why the tense is used in these sentences.
　　2 The form of the present perfect tense
　　3 Talt the uses of the present perfect tense
　　A We use the present perfect tense to talt things that happened in the recent past, but are connected to the present.
　　The disappearance of Justin has made Kelly very unhappy.
　　B We also use the present perfect tense to talt something that started in the past, and is still happening now.
　　I have not seen Justin since last Friday night.
　　C We use the present perfect tense when the exae of an action is not clear or important. We use it with time expressions such as:
　　already   ever   for  just   lately  never  recently  since   yet
　　We use already for affirmative statements and yet for negative statements.
　　We use for + a period of time and since + a point in time.
　　D We use the present perfect tense to talt actions that were pleted only a short time ago. In this case, just is used. Pay attention to the position of just.
　　He has just gone out.(=He went out a few minutes ago.)
　　We use the present perfect tense here to tell others that he isn’t here now.
　　I have just heard the news.(Now I know the news.)
　　E We can also use the present perfect tense for repeated actions, that is, we use the present perfect tense with the time expressions once/twice/three times…
　　F Actions occurring in an inplete period might be indicated by today or this morning /afternoon/evening/week/month/year/century or all day/night/week, all the time, always etc.
　　Tom has rung up three times this morning.(Now it is still in the morning.)
　　Tom rang up three times this morning.(Now it is not still in the morning.)
　　plete the following sentences with the proper tense.
　　A We have studied (study) English for about five years.
　　B They have lived (live) in the south since their daughter was born.
　　C I have read (read) your article three times. It’s well written.
　　D The student has finished (finish) her homework already.
　　E Eric has gone (go) back to his hometown today.
　　F The police have just finished (finish)searching the area.
　　4 pare the simple past tense and the present perfect tense
　　Look at the following sentences and point out what tense or tenses are used in them and the reasons why they are used.
　　A We have studied English for about five years. We began to study it five years ago