Must mustn't needn't

'You must do something' = bunu etməyin vacibdir:

• Don't tell anybody what I said. You must keep it a secret.
• We haven't got much time. We must hurry.

'You mustn't do something' = bunu etməməyin vacidir (buna görə bunu etmə):

• You must keep it a secret. You mustn't tell anybody else. (= don't tell anybody else)
• It's essential that nobody hears us. We mustn't make any noise.

'You needn't do something' = bunu etməyin vacib deyil, bunu etməli deyilsən:

• You can come with me if you like but you needn't come if you don't want to. (= it is not necessary for you to come)
• We've got plenty of time. We needn't hurry. (= it is not necessary to hurry)

Needn't əvəzinə don't/doesn't need to ifadəsindən də istifadə etmək olar:

• We needn't hurry.
• We don't need to hurry.

Needn't və don't need to ifadələri mənaca don't have to ifadəsinə oxşardır:

• We've got plenty of time. We don't have to hurry.

Needn't have (done)
Aşağıdakı misala baxaq:

George had to go out. He thought it was going to rain, so he decided to take the umbrella. But it didn't rain, so the umbrella was not necessary. So: He needn't have taken the umbrella.

'He needn't have taken the umbrella' = O çətiri götürdü, amma buna ehtiyac olmadı. Amma əlbəttə ki, o, bunu çıxanda bilmirdi.

Needn't (do) və needn't have (done) ifadələrini müqayisəedək:

• That shirt isn't dirty. You needn't wash it.
• Why did you wash that shirt? It wasn't dirty. You needn't have washed it.

Didn't need to (do) və needn't have (done)
I didn't need to... = bu mənim üçün vacib deyildi... (və mən bunu o vaxt bilirdim):

• I didn't need to get up early, so I didn't.
• I didn't need to get up early, but it was a lovely morning, so I did.

I needn't have (done) something' = Mən bir şey etdim, amma indi bilirəm ki, bu vacib deyildi:

• I got up very early because I had to get ready to go away. But in fact it didn't take me long to get ready. So, I needn't have got up so early. I could have stayed in bed longer.