一、介词1、在...里，在...上The two brothers study in the same class.两兄弟在同一个班里上课。The telephone is in the little study on the ground floor.电话在一楼的小书房内。2、在...之内；在...方面He is lacking in courage.他缺乏勇气。3、从事于；参加着She is in business.她做生意。4、穿着，戴着He is dressed in black.他穿黑衣服。5、朝，向She hurried away in the opposite direction.她朝相反的方向匆匆离去。6、(表示手段、方法、材料)用，以They paid in cash.他们用现金支付。7、在...期间；在...以后He'll come back in a week.他将于一周之后回来。I haven't met her in a long time.我好长时间没有遇见她了。8、处在...中The room was in disorder.房间里乱七八糟。9、(表示数量、程度、比例)按，以；在...中One child in twenty has this disease.二十个小孩中有一个患有这种疾病。10、在...身上，在...上In him I see a future leader.我在他身上看到了一个未来的领袖人物。11、（表示过程）在...当儿；在...过程中The work is in progress.这工作正在进行中。12、（表示动作的方向和结果）进入到...中；成，为He pushed a button and set the machine in motion.他按下按钮开动了机器。二、副词1、进；在里头Please come in.请进。2、在屋里；在家I called on him; but he wasn't in.我去拜访他，但他不在家。3、（车、船、季节等）已到达，已来临Spring is in at last.春天终于来了。4、（庄稼）已收进；已成熟The wheat crop is in.小麦收进来了。5、（服装等）时髦Miniskirts are in again.迷你裙又时髦起来了。6、当政；当选The Democratic Party is in.民主党执政了。三、形容词在里面的；朝里面的I found the letter in my tray.我在文件盘里发现了这封信。
