it sounds like the clutch is worn , is the clutch pedal coming up a fair bit higher than the brake pedal ? ,
how high does the pedal come up before the car starts to pull away it should only come up about couple of inches, to test it pull the hand brake on then try to move the car forward in first gear, is it pulling away or is the clutch slipping, if your not sure take it to your local garage and ask them to test it for you, i dont know any garage that will charge you for this service, hope this helps.
michael k, March 2012