Master Cylinder?

The problem with my 95 integra is that my clutch pedal has no pressure at all. Recently my clutch pedal suddenly had little pressure and sometimes would not disengage. So i bleed it a few times thinking it was probably just air in my lines. But the more i bleed it the worst it got. I have replace the master cylinder, and clutch. So i thought it might be the slave but i took my old one out (my friend said it probably was the slave) and look at it. It seems to be fine. Well my question is first could my master cylinder have went bad again?It was replace probably like 6months ago. I don't see any leaks in or out of the car but i may have missed something. Second could i have put the new slave cylinder in wrong? I'm not much of a mechanic and all the work done before was done by me and my dad. (he usually does all the work or just tells me what to do)

no pressure. CLOSELY inspect the slave and master, and lines.