你在拽我的腿吗
1)Are you kidding=Are you pulling my leg?
你在开玩笑吗?
Example:
-Do you know that Andy is going out with someone?
-What? Are you kidding? I am still a bachelor.
-So who is that girl walking along the street with you yesterday?
-My god! She is my sister and she has got married and her baby is 5 years old!
-Wow, your sister looks so young.