Sắp xếp:

1. glass/ cafeteria/ go/ the/ and/ a / of/ lemon/ juice / Mai/ let's/ to/ have

-> Let's go to the and have a glass of lemon juice, Mai.

2. piano/ is/ to/ the/ in/ music/ room/ Nam/ play/ learning

-> Nam is learning to play the piano in the music room.

3. be/ English/ pratise/ every/ to/ good/ it/ we /our/ day/ at

-> To be good at English we pratise it every day.

4. week/ club/ to/ am/ join/ the/ collector's/ next/ I/ going/ stamp

-> I am going to join the collector's stamp club next week.

5. theater/ play/ are/ a/ with/ school/ group/ they/ rehearsing/ their

-> They are rehearsing a play with their school theater group.

6. British/ a/ has/ large/ of/ stamps/ David/ collection

-> David has a large collection of British stamps.

7. anniversary/ a/ is/ orchestra/ going/ give/concert/ the/ at/ school/ celebrations/ our/ to

-> The orchetra is going to give a concert at our school anniversary celebrations.

8. stamps/ and/ I/ collect/ together/ Mary/ often

-> Mary and I often collect stamps together.

Give the correct form of the words.

1. I'll go out with Tom when he ...finishes... (finish) his homework.

2. As Quang ...comes... (come) here, my parents ...will wait... (wait) him in front of door.

3. He ...will send... (send) you some letters as he ...arrives... (arrive) in Hanoi.

4. I ...will go... (go) out if my sister ...stays... (stay) at home.

5. If you ...have... (have) time, I ...will visit... (visit) you.

Choose the best answer to complete these following sentences

1. There are 366 days in a ________ year.

A. late B. leap C. later D. double

2. I _____ tired now.

A. will B. will be C. am D. be

3. Hoa and Lan meet in front ______ the theater.

A. in B. with C. of D. at

4. Why is Mr.Tan ________?

A. worried B. worries C. worry D. worrying

5. The doctor will _____ you lots of questions.

A. ask B. say C. tell D. get

6. My ________ with her uncle on a farm now.

A. living B. to live C. live D. lives

7. I feel much ______ after taking those pills.

A. good B. better C. best D. bad

8. The pictures will ________ our bedroom lovelier.

A. do B. practice C. make D. play

9. Please ________ your hand if you want to answer the questions.

A. raise B. hang C. laugh D. put

10. I'll call you _______.

A. now B. at the moment C. tomorrow D. A & B are correct

\(\dfrac{1}{n}-\dfrac{1}{n+a}=\dfrac{n+a}{n}-\dfrac{n}{n+a}=\dfrac{a}{n\left(n+a\right)}\)

( -x + 31 ) - 39 = 69 + 11

( -x + 31 ) - 39 = 80

( -x + 31 ) = 80 + 39

-x + 31 = 119

-x = 119 - 31

-x = 88

x = -88

( 1x - 14 ) + ( -6 ) = 5

( 1x - 14 ) = 5 - ( -6 )

1x - 14 = 11

1x = 11 + 14

1x = 25

x = 25 : 1

x = 25

-37 - | 7-x | = -127

| 7-x | = -37 - (-127)

| 7-x | = 90

1) 7-x = 90

x = 90 + 7

x = 97

2) 7-x = -90

x = -90+7

x = -83

x = 97; -83

Ta có:

\(2\sqrt{5}\) = 4,472......

=> 4,472.... < 5 do đó \(2\sqrt{5}\)< 5

a)

- Vận tốc của thuyền với nc là V1

- Vận tốc của nước với bờ là V2

Vxuôi dòng = V1+V2

Vngược dòng = V1−V2

=> Vxuôi dòng > Vngược dòng

<=> txuôi dòng < tngược dòng

=> Nước chảy theo chiều từ A -> B

b)

V xuôi dòng = V1+V2

<=> S/txuôi.dòng = V1+V2

<=> V1+V2 = 6 (1)

Vngược dòng = V1−V2

<=> V1−V2 = 4 (2)

Kết hợp (1) , (2) giải hệ pt => V1 = 5 ; V2 = 1

c)

=> Vxuôi.dòng=Vngược.dòng

<=> V1+V2 = V1−V2 = 6

=> V1 = 7 (km/h)

Viết câu hoàn chỉnh với những từ gợi ý sau:

1. She/ do/ her homework/ every evening.

=> She does her homework every evening.

2. She/ not/ do/ her homework/ at the moment.

=> She isn't doing her homework at the moment.