to complete your homework, you must study the topic well.
A person should not know his purpose, but must feel it intuitively and strive to fulfill it.
The opponent should never know in advance how the ball will be returned.
since I had to watch my little sister, I didn't go out with my friends.
I must finish my business before I begin yours.
You must not raise your voice to adults.
you have to follow the rules at school.
If you feel unwell, you should see a doctor right away!
You shouldn't ask too much about it.
You didn't have to clean up by yourself.
you must wash the dishes before you leave!
you don't need to know about this.
Вроде так!