I'm happy to enlighten you Tash.
But first show me the rep!
OK Tash here we go....
Basically your body will get more and more used to alcohol, which is classes as a poison so eventually it will take you shed loads to get pissed (think beer belly) unless.... you drink in moderation or indeed switch to other drinks. If say.... you had the odd glass of booze during the week and then got hammered on a Saturday you will kind of stay at a level.
Another impact on how quickly you get pissed is food.
If you skimp on the food you will get pissed quicker but if you drink after a big meal you may not feel much of an effect.
Hope this helps!

**** you AB.