Ii. past simple or present perfect ? read and complete the text with the correct form of the verbs in brackets. stephen hawking is a world-famous scientist he ( (not win), a nobel prize yet. he (2) ) us more about time than anyone jn the world. he (5) be) interested in time and questions like 'how ( world (start)? ' and 'can we go back in time? ’ he (5) ) his famous book: about time in 1988 and it ( (already sell) more than eight million copies. stephen hawking (7) ) wheelchair for most of his life because he has als. this means that information that tells his arms and legs to move does not go up his spinal cord to his brain. so his arms and legs don't move and breathing is a problem. in 1985 he () to hospital because he couldn't breathe. doctors () him to breathe but they had to take out his voice. he now speaks with the help of an american computer. ‘the computer (10) __ (give) me a voice but it's an american voice, ’ stephen often says, with a smile.

1. hasn't won, 2, told, 3 has been. 4, did start, 5. wrote., 6. has sold, 7. was, 8, went. 9. helped, 10. gave.

)The waitress hasn’t brought  our tea yet .The waitress brought our tea a few minutes ago. 2)The bell  has just rung. The bell rang some minutes ago.  3)He has already gone   to London . He  went to London  last week. 4)The boys  played football in the yard yesterday. The boys have played football in the yard many times. 5)Mother has read  a new novel by Aitmatov this month .Mother read a new novel by Aitmatov  last year. 6)Students have already cleaned  their classrooms. Students cleaned their classrooms last Saturday. 7)The teacher has just explained  a new rule. The teacher explained a new rule at the pervious lesson. 8)Ann has just done her home work. Ann  did  her home work on Friday. 9)They  have discussed theis problem many times . They  discussed this problem a few days ago 10)Granny  has just made a birthday cake. Granny  made a birthday cake yesterday. 11)The birds have already flown  to the South. The birds  flew  to the South at the end of August. 12)The train  has just come .The train  came an hour ago. 13)Who has  just your friend spoken to?Who did your friend speak to yesterday?14)We have already written the words of Lesson 7.  We wrote the words of Lesson 7at the last lesson

1) The waitress brought our tea a few minutes ago. The waitress hasn't brought our tea yet.
2) The bell has just rung. The bell rang some minutes ago.
3) He has already gone to London.
He went to London last week.
4) The boys played football in the yard yesterday. The boys have played football in the yard many times.
5) Mother has read a new novel by Aitmatov this month. Mother read a new novel by Aitmatov last year.
6) Students have already cleaned their classrooms. Students cleaned their classrooms last Saturday.
7) The teacher has just explained a new rule. The teacher explained a new rule at the pervious lesson.
8) Ann has just done her homework. Ann did her homework on Friday.
9) They have discussed this problem many times. They discussed this problem a few days ago.
10) Granny has just made a birthday cake. Granny made a birthday cake yesterday.
11) The birds have already flown to the South. The birds flew to the South at the end of August.
12) The train has just come. The train came an hour ago.
13) Who did your friend speak to yesterday? Who has your friend just spoken to?
14) We have already written the words of Lesson 7. We wrote the words of Lesson 7 at the last lesson.