Question 1: What is your motivation for playing poker?
First of all I always be fascinated about "mind games" such chess, backgammon, "go", etc...
To be honest, the first motivation is the money, if I have to choose beween glory and fortune, I'll choose the of fortune for sure. 
Question 2: What are your weaknesses when playing poker?
I have difficults with the "math" aspect of the game.... It's hard for me to apply at the tables the concepts like pot odds, raise calcs etc..
Question 3: What does it mean to play tight-aggressive?
To be selective about when and which cards to play and be agressive when choose to play.
By the way.........
I'm sorry about my English....lol