لأن　= because of ني = me [ it's like أنا　] أنا عطشان = i am thirsty لعبت = played [ past form ] why i am thirsty ? because i played [ football for example ] لماذا أنا عطشان ؟ لأنني لعبت كرة القدم

Because am :D

Because I am. The lam here ل means because أننى meaning I أنا عطشان لأننى لعبت I am thirsty because I played. عطشان thirsty لعبت played