9,14,15,16,17,19. there are (những j có chữ s đằng sau) 

13,18,20. there is (những j có từ a,an hoặc k có chữ s)

4.how much

5.how many ( những j mà ta đếm đc)

( những j dạng chất lỏng hoặc có hạt nhỏ dùng đồ để đo) 6.how much orange....

6.how many work...

9.how much

7,8.how many

10.how many hours...

10. how many piano work...

III,

1,2,4,6,7,9,12,14,15,16,17,19: There are

3,5,8,10,11,13,18,20: There is

IV,Sửa lỗi sai

1.a - (chuyển thành) an

2.is - are

3.an - a/the

4.a - the

5.in - on

6.peoples - people

7.boxs - boxes

8.class - classes

9.there are - are there

10.are - is

11.shelf - shelves

12.glass - glasses

13.is - are

14.are - is

15.thiếu chữ 'are' đằng trước chữ 'go'

16.is - are

17.is - are

18.An - a

19.many - much

20.work - works

21.does - do

V,

1.How many notebooks are there on the table? - There are ten

2.How many pictures are there on the wall? - There are five

3.How many teachers are there in your school? - There are fourty

4.How many days in a year? - There are three hundred and sixty-five

5.How many windows in your classroom? - There are four

6.How much milk in the fridge? - There is 500ml

7.How many seasons in Viet Nam? - There are four

8.How many ethnic groups in Viet Nam? - There are fifty-four

9.How many festivals in your village? - There are many

10.How many pagodas in your province? - There is only one

VI,

1,4,6(1,2),9: How much

2,3,5,7,8,10(1,2) : How many