1. Ba and Tam usually go fishing.......on........ the weekends.

2. The students will visit the capital ........in...........the summer

3.They heard a very strange noise......at.......midnight

4. Our little brother took a long nap from 1p.m........till........4 p.m.

5.The competitions will take place. ......between........... 8 a.m and 12 a.m.

6. She talked............in............an hour to persuade her parents.

7. they have learned English.........for........many years

8. The boys often go skiing.........in............... the winter

Are you free from 2pm to 4pm on june 3

Are you free from 2pm to 4pm on june 3 ?

Ta có :

+) 4P_M + 2N_M + 4P_X + 2N_x = 164

<=> 4(P_M + P_X) + 2( N_M + N_X ) = 164 (1)

+) 4P_M - 2N_M + 4P_X - 2N_x= 52

<=> 4(P_M + P_X) - 2( N_M + N_X ) = 52 (2)

+) P_M + N_M - P_X - N_x = 23

<=> (P_M - P_X) + ( N_M - N_X ) = 23 (3)

+) 2P_M + N_M - 4P_X - 2N_x = 10

<=> 2(P_M - 2P_X) + (N_M - 2N_X ) = 10 (4)

Giải (1) và (2) :

P_M + P_X = 27 => P_M = 27 - P_X (5)

N_M + N_X = 28 => N_M= 28 - N_X (6)

Thay (5) vào (3) :

<=> ( 27 - P_X - P_X) + ( 28 - N_X - N_X ) = 23

<=> 27 - 2P_X + 28 - 2N_X = 23

<=> P_X + N_X = 16 (7)

Thay (6) vào (4) :

<=> 2(27 - P_X - 2P_X) + (28- N_X - 2N_X ) = 10

<=> 54 -6P_X + 28 - 3N_X = 10

<=> 2P_X + N_X = 24 (8)

Giải (7) và (8) :

P_X = N_X = 8

Còn lại bạn tự thay vào các phương trình (5) và (6) nhé

Chúc học tốt <3

Cù Văn Thái

Supply the correct verb forms

11) at 4pm yesterday? Well, i (work) in my office at that time.

WAS WORKING

12) sometime i (get up) before the sun( rise)

HAD GOT UP / ROSE

13) don't speak until someone (ask) you

ASKS

14) marry (come) from london

COMES

15) please be quiet! I (work)

AM WORKING

16) when i (be) a child i (want) to be a doctor

WAS / WANTED

17) Dan (be) born after his father (die)

WAS / DIED

18) Long ago, my younger brother after (cry)

CRYING

19) the last train (leave) the siation at 5pm.

LEFT

20) up to now the teacher (give) our class five test.

HAS GIVEN

43. although he took taxi, Bill still arrived late for the concert.

==> Despite..taking taxi, Bill still arrived late for the concert..

44. Theater seats can be booked by telephone.

==>You....can book theater seats by telephone........

46. I've never been to less exciting concert.

==>It was the least exciting concert I have ever been

47. '' I'll never come back here again,'' said the angry tourist.

==> The angry tourist..said he would never come back there again...

48. The red car is (Comparision)

=> the red car is more expensive than the blue car.

49. Because of being lost, we stopped to ask policeman for directions.

==>We......we stopped to ask policeman for directions because we were lost.........

50. We re worried because we have to live very far from our parents.

==>We wish.....we didn't have to live very far from our parents. ........

51. He hasn't been to the doctor's for over yers.

==> He hasn't had .....the doctor's for over yers.....

52. That old keyboard is not worth repairing.

==> It is pointless to.....repairing for that old keyboard......

It took him a long time to recover the accident a few days ago -> it took him a long time to recover from..the other accident he had a few days ago.. (other)

It took us so long to get home that we missed our supper-

It took us such a long time to get home that we missed our supper.-

We were so tired that we went straight to bed when we got home.-

We had such a tiring day that we went straight to bed when we got home.-

The room was in such a mess that it took two hours to tidy.-

The room was so untidy that it took two hours to sort out.-

He was such a fool that no one took notice of him-

He was so silly that no one took notice of him- 

It took us so long to get home that we missed our supper

It took us such a long time to get home that we missed our supper.

We were so tired that we went straight to bed when we got home.

We had such a tiring day that we went straight to bed when we got home.

The room was in such a mess that It took two hours to tidy.

 The room was so untidy that It took two hours to sort out.

He was such a fool that No one took notice of him

He was so silly that No one took notice of him

1. Videos help us very much in education.
-> Videos are...very useful for us in education.....

2. Our grandparents visited Ha Long Bay last summer.
-> Our grandparents paid.......for a visit to Ha Long Bay last summer.....

3. I like fried chicken. My sister does, too.
-> Both........my sister and I like fried chicken.............

4. That was a silly thing to say.
-> What...a silly thing to say...

5. Collecting old coins from foreign countries is one of George' s interests.
-> George is.......interested in collecting old coins from foreign countries..............

6. Rose likes apples more than bananas.
-> Rose doesn' t.....like bananas more than apples.......

7. Long is heavier than his brother.
-> Long' s brother doesn' t......heavier than long......

8. Minh didn' t have new clothesbecause his family was poor.
-> Because of........Minh's poverty, he didn't have new clothes.............

9. Last summer we went to Da Nang by air.
-> We took.......a plain to Da Nang last summer...........

10. We will make a Sapa tour that lasts for four days. -> We will make......................................................

It took us so long to get home that we missed our supper-

It took us such a long time to get home that we missed our supper.-

We were so tired that we went straight to bed when we got home.-

We had such a tiring day that we went straight to bed when we got home.-

The room was in such a mess that it took two hours to tidy.-

The room was so untidy that it took two hours to sort out.-

He was such a fool that no one took notice of him-

He was so silly that no one took notice of him-