To pull one’s leg 是一句英文俗语,

To pull one's leg 初看起来好像和中文里的"拉后腿"的意思差不多.但是真正意思是逗别人,开别人玩笑的意思.
例句:"My roommate said this girl had told him she wouldn't mind going out with me.But when I invited her to a movie,I learned he was just pulling my leg."
这个大学生说："我的同房间同学说,那个女孩愿意和我一起出去玩.可是,当我请她去看电影的时候,我才发现我那同学是逗我,开我的玩笑."