Negation of biti

In English, saying that something is not the case takes two words: I am becomes I am not. Serbian does it with one word. Each form of biti has a ready-made negative twin, and you simply use that instead.

One word instead of two

Look at the affirmative forms you already know, and at the negative form beside each one. The negative is just ni- stuck onto the front:

So Ja sam konobar (I am a waiter) becomes Ja nisam konobar (I am not a waiter). Nothing else changes.

Never write ne sam, ne je, ne su. Those look like a word-for-word translation of English not am, and they are simply not Serbian. The little word ne does negate other verbs, but biti has its own forms and refuses help.

The negative word is a strong word

In the last lesson you saw that sam, si, je, smo, ste, su are weak little words that can never open a sentence — something always has to come first. The negative forms are the opposite. They are strong, stressed words, and they are perfectly happy at the very beginning:

• Nisam lekar. — I am not a doctor.
• Nije ovde. — He is not here.
• Nisu studenti. — They are not students.

That is why you can drop the pronoun so easily here. Nisam kuvar is a complete, natural sentence; you only add ja when you want to stress me as opposed to somebody else.

Correcting someone

This is what the negative is for most of the time: somebody has got your job wrong and you put them right. Serbian usually puts the two halves side by side, negative first:

• Nisam konobar, ja sam kuvar. — I am not a waiter, I am a cook.
• Ona nije profesorka, ona je studentkinja. — She is not a professor, she is a student.

Notice the second half goes back to the weak form sam / je, which needs something in front of it — here the pronoun ja or ona.

Short answers

A yes/no question about someone's job is answered with the bare form, no other words needed:

• Ti si vozač? — Ne, nisam. (No, I'm not.)
• Oni su pekari? — Ne, nisu. (No, they aren't.)

Ne on its own means no, the answer. It is not part of the verb — notice the comma after it. Ne, nisam is No, I'm not, two separate things.