Ex1. 

1. Ho Chi Minh City is the most crowded city in Viet Nam.

5. Although Peter speaks English quickly, we can understand him.

6. If I pass my exams with good grades, my mum will give me a laptop.

7. I don't like this TV programme because it's so boring.

8. Don't play football in the street!

Ex2. 

1. If Sue doesn't hurry, she will miss the bus.

2. Rita will pass the exam if she studies hard.

3. If he watches too much television, he will hurt his eyes.

4. If it isn't sunny tomorrow, we won't go to the beach.

5. We will visit her if we have time.

6. I won't wait if you arrive late.

7. They won't play tennis tomorrow if it rains.

8. If you don't set your alarm clock, you won't wake up on time.

Ex3. 

1. Where did Linh read books yesterday afternoon? (in the library là địa điểm→where)

2. What mustn't I do in the classroom? ( drink and eat là hành động→what)

3. How often do you stay up late on Saturday night? (câu hỏi tần suất→how often)

4. When do many girls do aerobics? (at the weekend là thời gian→when)

5. When do your lessons start? (12.30 p.m là thời gian→when)

6. How many students are there in your class?  (49 là số lượng→how many)

7. How does her father go to work? (by bus là phương tiện→ how)

8. How long does it take Mr.Lan to walk to work? (fifteen minutes là thời gian→ how long)

9. How long haven't you seen her? (three days là thời gian→ how long)

10. Who has to wear uniform? (the woman là người→ who)

Ex4.

1. has never seen

2. Did you meet

3. visited

4. didn't open

5. wasn't/ would be

6. help

7. work

8. get

9. lend

10. hasn't done

11. fix

6. worries/ will be

7. didn't go/ stayed/ did

Ex5. 

1. I'm not really interested in Robotics.

2. Jack took part in a robotics competition last month.

3. This robot can cook a variety of different meals.

4. I couldn't email you because my computer didn't work last night.

5. When I was young, I could run very fast.

6. I didn't need to finish my homework yesterday.

7. She has worked at the school canteen for two months.

8. If you study hard, you will pass the exam.

Period 2:

Exercise 1:

1.→HCM City is the most crowded city in Viet Nam

5.→Although Peter speaks English quickly,We can understand him

6.→If I pass my exams with good grades,My mum will give me a laptop

7.→I don't like this TV programme because it's so boring

8.→Don't play football in the street !

Exercise 2:

1.→If Sue doesn't hurry,She will miss the bus

2.→Rita will pass the exam if she studies hard

3.→If he watches too much television,HHe will hurt his eyes

4.→If it isn't sunny tomorrow,We won't go to the beach

5.→We will visit her if we have time

6.→I won't wait if you arrive late

7.→They won't play tennis tomorrow if it rains

8.→If you don't set your alarm clock,You won't wake up on time

Exercise 3: 

1.→Where did Linh read books yesterday afternoon ?

2.→What mustn't I do in the classroom ?

3.→How often do you stay up late on Saturday night ?

4.→When do many girls do aerobics ?

5.→When do your lessons start ?

6.→How many students are there in your class ?

7.→How does her father go to work ?

8.→How long does it take Mr.Lan to walk to work ?

9.→How long haven't you seen her ?

10.→Who has to wear uniform ? 

Exercise 4:

1.Has never seen

2.Did you meet

3.Visited

4.Didn't open

5.Wasn't/Would be

6.Help

7.Work

8.Get

9.Lend

10.Hasn't done

11.Fix

6.Worries/Will be

7.Didn't go/Stayed/Did

Exercise 5:

1.→I'm not really interested in Robotics

2.→Jack took part in a robotics competition last month

3.→This robot can cook a variety of different meals

4.→I couldn't email you because my computer didn't work last night

5.→When I was young,I could run very fast

6.→I didn't need to finish my homework yesterday

7.→She has worked at the school canteen for two months

8.→If you study hard,You will pass the exam

chúc em học tốt!!!!