prep (1)(指地点)在……里(面)(at a point within the area，volume or shape of sth)：the highest mountain (longest river)～the world/Africa/China 世界上/非洲/中国最高的山峰(最长的河流);live～a small village/the south of France/London 住在一个小村庄里/法国的南部/伦敦;children playing～the street/the park 在街上/公园里玩耍的孩子;swimming～the pool/the river/the lake/the sea在游泳池/河/湖/海里游泳;～the corner of a room 在房间的角落里(比较：at/on the corner of the street 在大街的拐角处);sit～a chair 坐在扶手椅子上;have a stick～one's hand 手里拿着手杖;have a cigarette～one's mouth 嘴里叼着香烟;
 (2)(指动作)进入(into)：put the papers/the photograph～one's briefcase (a drawer/one's pockets) 把文件/照片放进公文包(抽屉/口袋里);get～the car 钻进汽车;go (run)～the house/the room 走(跑)进房子/房间;throw sth～the fire/the wastepaper basket 把……扔进火里/废纸篓里;dip one's pen～the ink 把笔尖浸入墨水里;
 (3)a)(指时间)在(during)：～the twentieth century 在20世纪;～1996/the 1990's 在1996年/20世纪90年代;～spring/summer/autumn/winter在春/夏/秋/冬季;～January/February/March 在1/2/3月;～the morning/the afternoon/the evening 在上午/下午/晚上;～the past/the future 在过去/将来;b)在……(一段时间)内(within the space of)：He learnt to drive (finished the task/wrote the whole book)～three weeks/two months. 他用三周/两个月学会了开车(完成了任务/写完了全书)。Rome was not built～a day.(prov)罗马非朝夕建成。c)在……以后(after)：He'll return～a few minutes/hours/days/months. 他将在几分钟/小时/天/个月以后回来。 She is going up to London～three day's time. 她三天后去伦敦。 The concert will begin～an hour from now. 音乐会一小时后开始。
 (4)构成整体或一部分，含有(forming the whole or part of sth;contained with)：seven days～a week一个星期有七天;100 cents～a dollar 一美元有100美分;There is a cover charge included～the total. 总额里含有服务费。
 (5)(指比率)(indicating ratio)：a slope/gradient of one～four 一比四的坡度/梯度;taxed at the rate of 12p～the pound 每一英镑须纳税12便士;One～five of the population could not read. 有五分之一的人口不识字。
 (6)穿(戴)着(wearing clothes，colours，etc)：dressed (clothed)～rags/green衣衫褴褛/穿着绿色的衣服;～uniform/plain clothes/mourning/armour 穿着制服/便衣/丧服/盔甲;～disguise化装;～high-heeled shoes/a silk skirt 穿着高跟鞋/丝绸裙子;a man～spectacles/a hat 带着眼镜/礼帽的男子;
 (7)(指环境)(indicating physical surroundings)：go out～the rain/the cold/the sun 冒雨/冒着严寒/顶着太阳外出;
 (8)(指状态或状况)(indicating state or condition)：～order/disorder/a mess 整齐/混乱/乱七八糟;be～poor health/deep poverty/trouble/great confusion 健康不佳/处于极度贫困之中/处于困境/迷惑不解;be～a hurry/a rage 匆匆忙忙/愤怒;be～danger/anger/love/retirement 处于危险之中/气冲冲/在恋爱/退休了;be～a panic/a bad temper惊恐/发脾气 be～good spirits/pain/despair 精神振奋/处于痛苦之中/处于绝望之中;The roses are～bud/flower/bloom 玫瑰含苞欲放/盛开/盛开。They met～public/secret. 他们公开/秘密会面。
 (9)(指形式、形状、排列或量)(indicating form，shape，arrangement or quantities)：sit (stand)～groups/rows/a circle 三五成群地/一排排地/围成一圈地坐着(站着);a novel～five parts 分为五部分的一本小说;work～twos/threes/pairs 两人一组/三人一组/两人一对地工作;(hair)～a pony-tail(头发)成马尾状;
 (10)(指介质，手段，材料) (indicating the medium，means，material，etc)：say sth～English/a few words 用英语说/简单地说一说;speak～a loud/low voice 大声/小声地说;write～code/ink/pencil 用密码/墨水/铅笔写;printed～italics/capitals 以斜体/大写字母印刷;paint～oils 用油彩画画;a statue～bronze 青铜制作的塑像;go up～the lift 乘电梯上去;pay～cash 用现金支付(比较：pay by check 用支票支付);
 (11)关于，在……方面(with reference to;regarding)：be alike (differ)～character/appearance 性格/外表一样(不同);be backward～the techniques 在技术方面落后;be strong (weak)～English/mathematics英语/数学好(不行);～principle/theory/practice 原则上/理论上/实际上;equal～strength/price 力量/价格相等;lacking～courage/common sense 缺乏勇气/常识;a country rich/poor～minerals 矿产丰富/贫乏的国家;be blind～one eye 一只眼失明;four feet～length/depth/diameter 长度/深度/直径为四英尺;There is no point～not telling her. 瞒她是没有道理的。He saw no harm～letting her read those books. 他认为让她读那些书没有害处。
 (12)(指职业，活动)(indicating sb's occupation，activity，etc)：～the army/navy/air force 在陆军/海军/空军服役;～business/insurance/politics/journalism/computers在商界/保险业/政界/新闻界/电脑业供职;
 die/be killed in action 阵亡：He was killed～action in France. 他在法国阵亡。
 in that 因为：The budget is unrealistic～that it disregards increased costs. 这个预算不现实，因为它没有考虑成本的增加。
 adv (1)(指位置)在里面(within a particular area or volume;inside)：run/walk/go/come/fall～跑进/走进/走进/进来/掉进;drink coffee with milk/sugar～喝加牛奶/糖的咖啡;call/ask/have/let sb～叫/请/让/让某人进来;get/move/push/put/throw sth～把某物弄/搬/推/放/扔进来;
 (2)(指人)在家(工作地点)(at home or at a place of work)：Nobody was～when they called. 他们去拜访时家里没有人。 Let's stay～tonight. 今晚我们待在家里吧。The president isn't～today. 校长今天不在。
 (3)(车、船)到达，进站((of vehicles，ships，etc)coming to;arriving at)：Is the train～yet? 火车进站了吗? The plane is due～at 6 o'clock. 飞机应该6点钟到。
 (4)(指庄稼或畜类)从田里收回(从牧场赶回)(brought back from the fields)：get～the crops 收割庄稼;The wheat crop is safely～. 小麦完好无损地收进来了。 The cows will be～for milking in half an hour. 半小时后奶牛就会被赶回来挤奶。
 (5)(指潮水)涨到最高位((of the tide)at or towards its highest point on land)：It's twelve o'clock. The tide must be～. 12点钟了，潮水一定涨上来了。 The tide is coming～. 正在涨潮。
 (6)(指信、明信片等)送(收)到(delivered to the destination;received)：Applications must be～by May 31. 申请书必须5月31日前寄到我处。 Papers should be～on Friday afternoon. 论文应于星期五下午交来。
 (7)时髦，流行(fashionable，popular)：Short skirts are～again 短裙又流行了。Bright colours are～this spring. 今春流行亮丽色。
 (8)(水果，鱼等)上市，可买到的((of fruit or fish，etc)on sale or obtainable)：New potatoes aren't～yet. 新土豆还没上市。 Apples will soon be～. 苹果很快就上市了。
 (9)当政，上台(elected to office)：Labour is～and the Conservatives are out. 工党执政，保守党在野。The union president has been～sine 1995. 这位工会主席从1995年当选一直干到现在。If the Workers' Party comes～at the next election，a lot of industry will be state-owned. 要是工党在下次大选中获胜上台，许多工业就会收归国有。
 (10)(指一些球类运动)落在界内，进球(inside the boundary lines so as to score a goal)：His service was～. 他的发球落在界内。 The ball bounced～.球弹落在界内。 The ball is～—we've got a goal! 球进了——我们得了一分!
 be in for (infml)1)将参加：I'm～for the 100 meters/the high jump/an examination.我将参加100米赛跑/跳高比赛/一项考试。2)将经历：I'm afraid we're～for a storm/a summer shower. 恐怕我们要遇上暴风雨/阵雨了。 be～for a nasty shock/a surprise/a difficult time/trouble 会大吃一惊/非常吃惊/日子不好过/遇到麻烦;
 be in for it 可能受到惩罚：Stop that noise at once or you'll be～for it. 赶快安静下来，不然你们会受惩罚的。
 be/get in on 参与，了解(infml)：Most of the staff want to be～on the new pension scheme. 大多数职员想参与新的养老金计划。He is～on her secret. 他知道她的秘密。
 be/come/go in and out of 经常进出：During the holiday the children were～and out of the house all day. 在假日里孩子们一天到晚进出不断。
 be (well) in with sb 与……要好：He is well～with his boss/the Board of Directors. 他跟老板/董事会的关系很好。
 have/get it in for sb想报复，对……怀有恶意(infml)：After John beat Ted in a fight，Ted always had it～for John. 约翰打了特德之后，特德总想报复。
 day/year in，day/year out 日复一日/年复一年;For a whole year I have worked day～，day out，without a holiday. 整整一年我日复一日地工作，没有假日。
 adj (1)里面的，往里的(being within or leading toward inside)[作attrib]：an～patient 住院病人;go through the～door 穿过向里开的那扇门;
 (2)流行的，时髦的(popular;fashionable)[作attrib]：an～thing to do 做时髦的事;the～place to dine 时髦的餐馆;
 n (1)执政者(a person，group that is in power，in office)[C，通常pl] the～s and the outs 执政党与在野党;The election made him an～. 选举使他上了台。
 (2)宠信(favour)[C]：He has an～with the boss. 他得到老板的宠信。 enjoy some sort of～with the manager 得到经理的某种赏识;
 the ins and outs (of sth) 1)详情，细节：know all the～s and outs of the plan/a problem/legal procedures 了解这个计划/一个问题/司法程序的详情; 2)(道路的)曲折，(河流的)迂回：the～s and outs of a road 道路的弯弯曲曲;
 【辨异】1)in(指时间)与at的区别见AT。 2)in(指地点)与at和on的区别见AT。