To cry in one's beer,的意思是坐在酒吧间里对着啤酒哭,自己可怜自己。比如说,一个人在劝他的朋友:
例句-1: Come on, Joe! Instead of sitting around in a bar all day crying in your beer about not having any money, why not get off your bottom and go out and look for a job!
例句-2: I'm tired of hearing my roommate crying in his beer about how hard it is to get good grades. If he'd stay home and study instead of going out every night, I'm sure he'd do a lot better in his classes.
例句-3: Come on, Jack, you're twenty years old--don't be such a cry baby about everything. We all have our problems, but you ought to do something about them instead of just complaining.
例句-4: Bill, don't be such a cry baby about going to the dentist: all he's going to do is clean your teeth. Look at your little sister--she's not making a fuss about it.