M: Alright. There's a cafe on the corner over there, I think it's open 24-7.
L：对，前面就有家咖啡馆。你说那个cafe 24-7, 24-7是什么意思呀？
M: I said it's open 24-7. You know the number 24, and seven, right? 24-7 means it is open all the time.
M: You've got it! In the U.S. a lot of small diners, convenience stores and gas stations are open 24-7.
M: Not at all! It can be used for anything. For instance, Li Hua, if you ever have an emergency, you can call me any time, 24-7.
M: Yeah, that's probably a better idea. 911 operates 24-7. Li Hua, can you use this phrase now?
L：让我想想。有了。期终考试前，我肯定很多人为了准备考试，交报告晚上开夜车，所以可以说：Many students worked 24-7 before the finals. 对不对？
M: You're right. I was also up 24-7 studying and writing before the finals.
M: That's right! Woo Hoo! Hey, after we eat, let's go dancing somewhere.
M: Now that we are on vacation, I'm ready to party 24-7!
M: Well, duh, Li Hua! The lights are on and there are people inside. What do you think?
M: No, I didn't say anything bad! All I said was "duh". When someone says something that you think is very obvious, or asks you a stupid question, you can say "duh".
M: Duh, Li Hua. Of course they have coffee here. Practically every restaurant in the States has coffee.
L：Michael，我只不过随便问一句，你就又来duh, duh, duh……真讨厌！
M: Oooh! Sounds like you are getting a little grumpy, Li Hua. I guess you are pretty tired, huh?
L：Duh, Michael! 现在都已经半夜一点半了，你还问我累不累？我才该对你说“duh”！
M: Ok, Ok, calm down. I'll just get a coffee to go, and give you a ride home. It sounds like you need some sleep.
M: I see you are not the kind of person who like to party 24-7!