Leonard: I'm sorry. The bride and groom seem happy.
Amy: Why shouldn't they be? They have a feverish night of socially-approved copulation ahead of them. In some cultures, we'd stand outside of their bedroom cheering as they achieved orgasm.
Leonard: That sounds like a late night, and I have work in the morning, so...

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

Amy: The only person who signed my yearbook was my mother. "Dear Amy, self respect and a hymen are far better than friends and fun. Love, mom."

Bernadette: Good Morning, handsome.
Howard: Good morning, mom.
Bernadette: It's me!

Amy: I have a sorta kinda boyfriend at home playing with a model train, but you don't hear me bitching about it.