Does a nikon D3100 come with a lense or do i have to buy one separately?

Does a nikon D3100 come with a lense or do i have to buy one separately?

You need to read the sale advertisement that if the camera is BODY or with lenses.

The Nikon is usually sold in kit form which is with lens. Only thing you really need to add is a memory card.
I always advice newbies to buy:
- sd memory card, 8gb class 6, brand doesn't matter much
- some sort of protective bag
- a microfiber cloth
- a rocket blower

If you buy the camera in kit form it'll come with an 18-55 lens.