S² nhất (adj ngắn)

-My mom is the greatest person in the world.

- Bikes are the slowest of the three vehicles.  
- My village is the quietest place in the province. 

-My house is the smallest.
-This is the longest road.

S² nhất (adj dài)

-Linh is the most intelligent student in my class.

-The lion is the most dangerous animal of the three. 
-The brown dress is the most expensive. 

-She is the most beautiful girl I’ve ever met. 

-He drives the most carelessly among us.

Must

- You must study hard in school.

- You must keep silent in class

- You must lisen a lesson

- You must study English better.

- You must do your homewwork.

Mustn't

-She mustn't say that with her teacher.

-You mustn't using phone in class 
-You mustn't talk in class 
-You mustn't joking in class 

-We mustn't pick flowers in the school garden.

Today is the hottest in the year

Today is the coldest in the year

This room is the largest in the house

This house is the smallest in the town

The dog is the biggest in the country

You must take a boat trip

we must arrive on time
 you must study ENglish better.
 you must do your homewwork.

you must go to school on time

You mustn't  play football in school yard

We mustn't pick flowers in the school garden.

You mustn't throw trash or draw on the walls.
 You mustn't copying your friend's homework.
 You mustn't fight with your friends

She is the most beautiful

Quynh Son Secondary school is the most beautiful

He is the most talkative

She ís the most fantastic

Pagoda is the most fantastic

                               Chúc bạn học tốt :))