1. This mountain is the highest in the world.

2. Which is the longest river in the world?

3. Trang is the most intelligent in the class.

4. He is the cleverest of all.

5. He drives carefully.

6. She is the best singer in our country.

7. He is the fattest in the village.

8. This is the most beautiful girl i have ever met.

A = 1 + 3 + 3² + ... + 3¹⁰

3A = 3 + 3² + ... + 3¹¹

3A - A = 3¹¹ - 1 

2A = 3¹¹ - 1

Thay vào đề : 

3¹¹ - 1 + 1 = 3ⁿ

3¹¹ = 3ⁿ

=> n = 11

1. bought

2. joined-was

3.meet-to go

4. started

5.reading

6. pay

7. to be

8. not play

9. going

10. laugh

1+ e

2+d

3+a

4+b

5+c

My dream house will have some robots. They will do the housework.

What does your brother do in his free time? He plays games.

What did she do last night? She helped her mom.

Tom usually catches the bus to go to work but today he is driving.

Your parents worked in this factory when they were young.

How long does it take you to complete the lesson?

Look! Mary is skipping rope with her friends.

Is your friends making a cake at the moment? No, she is cooking meal.

I was a student. I study hard.

My hometown will have a new bridge next year.

musicians

in one day -> one day