Sinking clutch pedal. on 2004 Chevrolet Cavalier

My clutch pedal is sticking to the floor! I can pump on it with my foot repeatedly to get it to spring back up but then it will go out rather quickly, lately within seconds. Well I was wondering what would cause this? Faulty slave cylinder, maybe? I took it in to a transmission guy, a month or so ago, who bled the hydraulic line which fixed it for a couple days or so but now I have to practically jump on it at every stop light just to be able to put it in gear when I shift. I think it's a pressure problem but am not sure. Please Help!!

Asked by for the 2004 Chevrolet Cavalier
Sounds like a pressure problem alright. Keep in mind the same hydraulic fluid (brake fluid) that would have caused the clutch master cylinder or slave cylinder will probably have caused deterioration of the other unit. Check for obvious signs of leakage particularly at the rubber boot at the back of the master cylinder if it is leaking you may see fluid at the clutch pedal.