HELLO

Hi everyone, I'm new here. My question is this: I have a BMW 330i and sometimes if I accelerate quickly, the engine revs high but the car won't move. It only moves when the revs drop. It doesn't happen every time. Once, while going uphill, when I tried to reverse, it wouldn't move at all, and after several attempts, I smelled something burning. Could it be the clutch? Otherwise, it seemed to be working fine. Thanks

Indeed, it is the clutch that has wear on its brake lining and it slips (skids), that's why there is a burning smell.