câu 1:

a) 500-(300)-190+(-210)

b) (-3)³ .5+12.(-6)

c) 15.(-19-4)-19.(15-4)

câu 2: tìm x thuộc Z

a) 3x-2=3

b) x chia hết cho 5 và -7<x<11

Exercise 4: Chia động từ trong ngoặc1.Let’s go out. __________________ ( it/not/rain) now. 2.Julia is very good at languages. She _________ ( she/speak) four languages very well. 3.Hurry up! _____________ ( everybody/ wait) for you.4._____________ ( you/listen ) to the radio. “ No , you can turn it off” 5._______________ ( you/listen) to the radio every day ? “ No, just occasionally”6.The River Nile ______________ ( flow) into the Mediterranean. 7.The river ______________ (flow) fast today – much faster than usual.8.___________ (we/ usually/grow) vegetables in our garden, but this year ____________ ( we/ not/ grow) any.9.How is your English ?Not bad. I think _____________________ ( it/ improve) slowly. 10. Can we stop walking soon ? ________________ (I/start) to feel tired.

Exercise 3:Kiểm tra phần chữ nghiêng xem có lỗi ngữ pháp hay không?

1.Water boils at 100 degrees Celsius. 2.The water boils. Can you turn it off ?3.Look ! That man tries to open the door of your car. 4.Can you hear those people? What do they talk about ?5.I must go now. It gets late.6.I usually go to work by car.7.Hurry up! It’s time to leave. OK, I come.8.I hear you’ve got a new job. How do you get on ?9.Paul is never late. He’s always getting to work on time.10.They don’t get on well. They’re always arguing.

correct the sentences. Each sentences has one  mistake only 

a. I like playing video game and usually play with my cousins when I visit my aunt's house.

b. I don't like dancing. It's enough difficult. Can you dance?

c. I don't like collecting stamps, I prefer doing another things. do you enjoy collecting stamps? 

d. I enjoy learning to play guitar at home.

e. we don't like take photographs. What about you?

f. I'm not sure what I can tell about this picture

g. I really like picking up stamps.

h. I enjoy playing video games in my own