Michael和李华今天早上都有课，现在正往课堂走。李华今天会学到两个常用语：to goof off 和to hit the sack。
L：Michael，别往我头上扔雪块，行吗？你怎么象个小孩呀！
M: Li Hua, I'm just goofing off.
L：你就是讨厌。我不懂什么是goofing off.
M: Actually Li Hua, to goof off does mean that I'm acting stupid and not being serious. Goof is a verb.
L：噢，to goof off 就是干无聊的事，那你确实很无聊，老向我扔雪块。
M: To goof off is a great term. Young people use it a lot. It is often used to describe how young people are behing.
L：年轻人经常用to goof off来形容别人的行为？我记得念中学时班上有个学生老是打断老师的话，喜欢开玩笑，你可以说这个学生是goofing off吗？
M: Yeah, that's right. Children or young people often goof off. Do you remember when we were at the movies and those high school students threw candy at the screen, you could say they were goofing off.
L：对，没错，小孩和年轻人经常会做一些无聊的事开玩笑。我才不会忘掉我们那次去看电影的事呢。那几个中学生往银幕上扔糖果，真是太无聊了，他们还以为好玩呢。
M: To tell you the truth, when I went to the library in high school with my roommates we would usually waste time and ended up goofing off.
L：你是说，你念中学时跟同学去图书馆念书，结果在那儿互相扔纸球？
M: Yeah, that's right.
L：怪不得你一开始考不上大学呢！行，教室到了，下课等我一起去图书馆，可千万不要goof off。
L：这课真是枯燥无味。我最讨厌晚上上课，每次上完课，我都感到很累。
M: That's right. Even though it's not that late, I'm ready to hit the sack!
L：你说什么？你要去捅一个口袋？Sack不是麻袋吗？我以为你很累了，而你现在要去运动？
M: No, no. It's a colloquial saying. I mean I'm going to bed. Sack, here means bed, and hit means going to.
L：噢，原来to hit the sack是指去睡觉，sack在这里是指床，hit是去床上睡觉的意思。那我要坐下，能不能说to hit the chair?
M: No, not really. This phrase -- to hit the sack -- has a pretty limited meaning.
L：哟，to hit the sack只能指去睡觉，别的地方还不能用！那要是我午想睡个午睡，能不能说：I want to hit the sack?
M: No, it's usually used to talk about going to bed at night, after a long day at work or school.
L：午睡也不能用，只能指一天工作和学习后晚上去睡觉。那现在我已经上了一天的学，再加上晚上上了这堂枯燥无味的课，我可以说：It's time for me to hit the sack。对不对？
M: That's correct, Li Hua. But don't fet that we he a test tomorrow.
L：我当然不会忘掉明天的考试。
M: Ok, now go hit the sack, but after tomorrow's test we will he to study seriously for next week's test, no more goofing off.
L：明天考试后你想好好学习，为下星期的考试作准备。没问题，我帮你准备，我们俩都会考得很好。
M: Yeah, I'm going to hit the sack. Bye, Li Hua!
Michael 今天教了李华两个常用语，一个是：to goof off，意思是做一些无聊的事，开玩笑；另一个是：to hit the sack，这是指晚上上床睡觉。
