no offense/offence

　　“无意冒犯”(It’s used to say that you do not mean to upset or insult somebody by something you say or do). 例如：

　　No offense, but I’d really like to be on my own.

　　I'm sure he meant no offense when he said that.

　　如果你想说“没关系，没有觉得被冒犯到”，可以说None taken.

　　beat

　　这个单词有太多意思，这里是to be too difficult for somebody。例如：

　　It beats me = I don’t know.

　　What beats me is how it was done so quickly (= I don’t understand how).

　　flunk

　　这个听起来就不是什么好词儿= to fail an exam, a test or a course。比如：

　　I flunked math in second grade.

　　如果说因为总挂科被学校劝退，可以用flunk out of college = to have to leave a school or college because your marks/grades are not good enough. 例如：

　　He flunked out of college after four semesters.