Exercise 4 . Present perfect

Example :

Speaker A : how many tests have you taken since you started coming to this class ?

Speaker B : I have taken 3 tests since I started coming to this class . Or I haven't taken any tests since I started coming to this class

1. How many books have you ?bought since the beginning of the year / this tern ?

2 . How many letters / e-mail have you gotten so far this month / week?

3. How many letters/ e-mail have you written since the beginning of the month / week ?

4 . How many questions have I asked to far ?

5 How many times have you flown in an airplane?

6. How many times have you ....?

7. How many people have you met since you came here ?

Nối các nội dung ở cột A với các nội dung ở cột B cho phù hợp với vai trò của mỗi loại chất đối với cơ thể.