\(2n^3-38n=2\left(n^3-19n\right)=2\left(n^3-n-18n\right)=2\left(n\left(n^2-1\right)-18n\right)=2\left(n\left(n-1\right)\left(n+1\right)-18n\right)\)

vì n,n-1,n+1 là 3 số nguyên liên tiếp \(n\left(n-1\right)\left(n+1\right)⋮3\)

   n,n-1 là 2 số nguyên liên tiếp \(\Rightarrow n\left(n-1\right)⋮2\Rightarrow n\left(n-1\right)\left(n+1\right)⋮2\)

\(\Rightarrow n\left(n-1\right)\left(n+1\right)⋮2\cdot3=6\)

\(18⋮6\Rightarrow18n⋮6\Rightarrow n\left(n-1\right)\left(n+1\right)-18n⋮6\)

\(2⋮2\)\(\Rightarrow2\left(n\left(n-1\right)\left(n+1\right)-18n\right)⋮2\cdot6=12\Rightarrow2n^3-38n⋮12\)(đpcm)

- Which is your school ?= Trường nào là trường của bạn ?

- What school is it ?=- Đó là trường nào?

Trường nào là trường bạn ?

Trường bạn là trường nào ?

(gần giống đấy)

-Đâu là trường của bạn?
- Đó là trường nào?

Topic 1:

Honestly, I love living in the countryside. Some people would say that living in the city is better than living in the countryside. Advanced technology, convenient transportation, high quality education and good health care are few things what they enjoy about living in the city. Although living in the city has many advantages, I generally prefer living in the contryside. Because, in countryside, the life is very peaceful, quiet and safe. Also, the friendly and generous people, who will welcome you or help you at anytime. Especially, nobody can deny the fresh air in countryside since it has fewer vehicles. Each has a different lifestyle. It is singularly the decision of each person where they will live. For me, living in a countryside is the best.

Topic 2:

My favorite subjects in school are math and science. Math is my favorite subject because it is fun. It is like a mystery to find the answer. It can be challenging and can take steps sometimes. I like science too because it is about discoveries. One reaction can create another reaction. If the people that are doing the experiment are not careful, they may get the wrong reaction.
Many different jobs use math and science. Science is used to find cures for people who are sick. Doctors and nurses use math to measure how much medicine to give to people. Salespeople need to know math to count money. Architects need to know math to design buildings. Pilots use these subjects to fly a plane. All of these people use math and science daily to measure, pay and count. Math and science are needed and used all around the world. That is why math and science are so important.

Topic 3:

My favorite sport is playing badminton. There are four reasons why I like it. Firstly, I can improve my health through playing it. I play it about 2 times every week. It makes me feel energetic everyday. Secondly, I enjoy the feeling that badminton flies in the air. I can change the movement direction of badminton without much effort and make opponent lose it. Thirdly, I can make many friends when I play badminton. I often play it with many kinds of persons. We can improve our skills with exercises. Also we talk about many interesting things when we have an break. Finally, playing badminton is not as intense as other sports such as basketball and soccer. It lessens the possibility of being hurt. So If you like playing badminton, please feel free to contact me. I think we can exchange experiences and make friends.

câu đầu tiên sửa lại là: Fishing is a very common recreational activity .... vì từ activity là danh từ đếm được số ít

longs 0,5 month ---> lasts 0,5 month

fishes ---> fish (nếu viết là fishes thì được hiểu là món cá)

simply ---> simple

much experiences ---> many experiences

take a medicine ---> take medicine

II.

3.....very well

III.

7.D

8.C

2.C

mk chỉ biết chừng đó thôi

40 m đường gấp 8 m đường số lần là:

40 : 8 =5(lần)

Sửa 40 m đường thì cần số người là:

3 x 5=15(người)

Đ/S:15 người

Học tốt!

My name is Nguyen Minh Trung. I am a ___new__ student in a class 7A. I am from Da Nang and my family __still___ live there. In Ho Chi Minh City , I live __with___ my grandparents at 21/3B Nguyen Trai Street. My new school is not __far___ from our house - about one kilometer , so I __go___ to school by bike. There are __a lot of___ students in my new school. But i don't have __any___ friends . I am unhappy . I __miss___ my parents , my sister and my friends in Da Nang.

1. What is his full name ?

-> His full name is Nguyen Minh Trung.

2. Is he a new student ?

-> Yes, he is.

3. Where is he from?

-> He's from Da Nang.

4. Who is he living with?

-> He is living with his grandparents.

5. What is his address?

-> His address is 21/3B Nguyen Trai Street in Ho Chi Minh City.

6. How far is it from his house to school?

-> It's about one kilometer.

7. How does he go to school ?

-> By bike.

8. Why is he unhappy?

-> Because he misses his parents, his sister and his friends in Da Nang.

My name is Nguyen Minh Trung. I am a new student in a class 7A. I am from Da Nang and my family still live there. In Ho Chi Minh city, I live with my grandparents at 21/ 3B Nguyen Trai street. My neww school is not far from our house - about one kilometer, so i go to school by bike. There are a lot of students in my new school. But i don't have any friends. I am unhappy. I miss my parents, my sister and my friends in Da Nang.

1 What is his full name?

=> His full name is Nguyen Minh Trung.

2 Is his a new student?

=> Yes, he is.

3 Where is he from?

=> He is from Da Nang.

4 Who is he living with?

=> He is living with his grandparents.

5 What is his address?

=> He live at 21/3B Nguyen Trai street.

6 How far is it from his house to school?

=> About one kilometer.

7 How does he go to school?

=> He goes to school by bike.

8. Why is he unhappy?

=> He unhappy because he doesn't have any friends at new school. But he will miss his parents, his sister and his friends in Da Nang.

các bạn giúp mình nha mình đang cần gấp!

suply the correct form of the words in brackets top complete each sentence

1.My mother is kind and.........friendly.............(FRIEND)

2.Sahara is the..........hottest...... desert in the world. (HOT)

3.Ha Long Bay is VietNam's most beautiful......... (WONDER)

Đề Của Câu 3 Mình Thấy Sai Sai, Mình Nghĩ Nó Phải Như Thế Này Chứ:

Ha Long Bay in Viet Nam is the most beautiful wonderful

4.My school starts at 7a.m and ........finishes..............at 11.10 every day (FINISH)

My name is Nguyen Minh Trung. I am a new student in class 7A. I am from Da Nang and my family still lives there. In Ho Chi Minh City, I live with my grandparents at 21/3B Nguyen Trai Street. My new school is not far from our house- about one kilometer, so I go to school by bike. There are a lot of students in my new school. But I don’t have any friends. I am unhappy. I miss my parents, my sisters and my friends in Da Nang.

*Answer the questions: (1m)

1. What is his full name ?

->..............Nguyen Minh Trung..........................................................................................

2. Does she miss her parents and her sisters ?

Yes, she does