VI

1.in → at

2.is → are

3.minutes→minute

4.to → ∅ 

5.hearing → to hear

6.in → ∅ 

7.cause → make

8.was → did

9.the → ∅

10. country → countries

VII 

1.How far it is from Lan's house to the post office 

2.Mai is unhappy because she misses her parents much

3.Who is the tallest person in your gruop ?

4.Let's go swimming in that lake

5.Nga's mother wrote a sick note for her yesterday

6.You must wash the sipnach carefully

7.He could play the guitar  when he was small

8.My brother prefers watching TV to reading books

10.My friends works fewer hours than I do  

$VI.$

1. in→at

2. is→are 

3. minutes→minute

4. to→∅

5. hearing→to hear

6. in→∅

7. cause→make

8. was→did

9. the→∅

10. country→countries

$VII.$

1. How far is it from Lan's house to the post office?

2. Mai is unhappy because she misses her parents much.

3. Who is the tallest person in your group?

4. Let's go swimming in that lake.

5. Nga's mother wrote for her a sick note.

6. You must wash the spinach carefully.

7. He could play the guitar when he was small.

8. My brother prefers watching TV to reading books.

9. Very few people in Viet Nam had TV sets 30 years ago.

10. My friend works fewer hours than I do.