Transmission does not go in drive but works in other gears perfectly.

What is your question?

My 2000 Buick Century has a problem with it not going into drive. It will only shift to 1st, 2nd, and 3rd and in reverse and the car's transmission pulls with no problem in those gears but soon as I put it in drive it does not pull. It only revs up like its in neutral. Can anyone please tell me what it might be???