Dr. Koothrappali: Now, hold on. If she is dating an American, that's not a bad way to go. He's Jewish. Those chaps are very successful, and they don't drink a lot.

Penny: So, Dr. Koothrappali, long flight?
Dr. Koothrappali: Twenty hours.
Penny: Ooh, that's rough.
Dr. Koothrappali: Not at all. Did you know that when you fly Transcontinental without your wife, you don't pray for the plane to crash?

Dr. Koothrappali: Relax? Easy for you to say. Your mother isn't cleaning out your bank account. Forty years, the woman never cleaned a thing.

Bernadette: But I thought I'd be more excited.
Dr. Koothrappali: Oh, being excited isn't a guarantee of anything. Rajesh's mother was thrilled when she was pregnant with him. After he was born, she doted on his every move. And you know what happened? He broke her heart, moved halfway around the world, and dates only poor white women. So you never know.

Raj: Shut your ass!

Sheldon: If you don't mind, I'd like to stop listening to you and start talking.

Sheldon: I must say, Amy, pretending to have intercourse with you has given me a great deal of satisfaction.