Unit 1《Past and present》Grammar
Grammar
Present perfect tense
1. We use the present perfect tense to talk about an action that started in the past and continues to the present.
I have lived here since I was born.
2. We use the present perfect tense to talk about an action that happened in the past and has a connection with the present.
Eddie has just eaten Hobo's food.
(Eddie ate the food, and now Hobo has nothing to eat.)
3. We also use the present perfect tense to talk about how many times an action has happened till now.
I have already read this book many times.
We can use these time expressions with the present perfect tense.
 already  yet   ever
 never   just   recently
 since   for
We make positive statements in the Present Perfect tense like this:
I/You/We/They have + arrived.
He/She/It has + arrived.
We make negative statements in the Present Perfect tense like this:
I/You/We/They have not + arrived.
He/She/It has not + arrived.
 have not = haven't
 has not = hasn't
Have I/you/we/they + arrived?
Has he/she/it + arrived?
Yes, I/you/we/they have.
  he/she/it has.
No, I/you/we/they haven't.
  he/she/it hasn't.
We form the past participles of regular verbs by adding -ed, just as what we do to form the simple past tense of these verbs.


  
    
      Most verbs
      +ed
      finish→finished
    
    
      Verbs ending in -e
      +d
      change→changed
    
    
      Verbs ending in a consonant +y
      -y+ied
      carry→carried
    
    
      Short verbs ending in a vowel + a consonant
      double the consonant +ed
      stop→stopped
    
  


We form the past participles of irregular verbs differently. Here are some examples.

  
    
      No change
      come→come  hurt→hurt
    
    
      Change the vowel
      hold→held  win→won
    
    
      Change the consonant
      lend→lent  build→built
    
    
      Change the vowel(s) and the consonant(s)
      catch→caught  keep→kept
      forget→forgotten  tell→told
    
    
      Others
      be→been  have→had
      fall→fallen  fly→flown
      draw→drawn  see→seen
    
  


A short test
A: Mr Wu wants the students to practise using the present perfect tense. Help them write the past participles of the verbs below.
1. borrow ________  5. plan ________   9. say ________
2. hope ________   6. cry ________   10. grow ________
3. make ________   7. send ________   11. hit ________
4. get ________    8. watch ________  12. enjoy ________
B: Mr Wu asks the students to complete the sentences below using the present perfect tense. Help them complete the sentences.
1. They ______(finish) their homework already.
2. John ______ never ______(visit) China.
3. Mr Li ______(repair) over the bicycles since Monday.
4. We ______(not see) each other for years.
5. My parents ______(not come) back yet.
6. Our teacher ______(teach) us a lot about the history of China.
Chat time
C: Millie and Sandy are talking about a film about the history of Beijing. Complete their conversation with the correct forms of the verbs in brackets.
Millie: (1)______ you ______(see) any films recently, Sandy?
Sandy: No, I haven't. What about you?
Millie: I (2)____________(see) one last Saturday.
Sandy: What's it about?
Millie: It's about the changes in Beijing over the past century. From this film, I (3)____________(learn) more about Beijing's past and present.
Sandy: Oh, I think I (4)____________(hear) about the film. Do you plan to see it again?
Millie: Yes, I'd like to.
现在完成时的时间副词和时间短语：
1、副词already和yet。already一般用于肯定句中，yet一般用于否定句和疑问句中。
如：We have already finished our homework. 我们已完成作业了。
  They haven't finished their homework yet. 他们还没有完成作业。
2、副词ever和never。多用于否定句或疑问句中，表示“曾经”或“从未”等。
如：- Have you ever been to the Great Wall?
   你曾经去过长城吗？
  - I have never been to the Great Wall.
   我从未去过长城。
3、用just表示到说话时为止的时间状语。
如：I have just seen her, but I don't know where she is now.
  我刚看见她，但我不知道她现在在哪。
  He has just eaten ten apples.
  他刚吃完十个苹果。
用already, just, yet, ever, never, before（句末）等填空。
I _________(do) my homework already.
He _________(not finished) his homework yet.
_________ you ever _________(be) to Beijing?
We _________ never _________(see) such an exciting match before.
Mother _________ just _________(clean) the house. Please don't come in.
Find out the Present Perfect Tense in Times have changed.
1. I've lived here since I was born.
2. Have you ever moved house?
3. ... we've lived in this area since then.
4. Has the town changed a lot over the years?
5. It has become impossible for us to see each other as often as before.