介词的用法口诀早、午、晚要用in，at黎明、午夜、点与分。

年、月、年月、季节、周，阳光、灯、影、衣、冒in。

将来时态in...以后，小处at大处in。

有形with无形by，语言、单位、材料in。

特征、方面与方式，心情成语惯用in。

介词at和to表方向，攻击、位置、恶、善分。

日子、日期、年月日，星期加上早、午、晚，收音、农场、值日on，关于、基础、靠、著论。

着、罢、出售、偷、公、假，故意、支付、相反，准。

特定时日和"一……就"，on后常接动名词。

年、月、日加早、午、晚，of之前on代in。

步行、驴、马、玩笑on，cab，carriage则用in。

at山脚、门口、在当前，速、温、日落、价、核心。

工具、和、同随with，具有、独立、就、原因。

就……来说宾译主，对、有、方状、表细分。

海、陆、空、车、偶、被by，单数、人类know to man。

this、that、tomorrow，yesterday，next、last、one。

接年、月、季、星期、周，介词省略已习惯。

over、under正上下，above、below则不然，若与数量词连用，混合使用亦无关。

'beyond超出、无、不能，against靠着，对与反。

besides，except分内外，among之内along沿。

同类比较except，加for异类记心间。

原状because of,、owing to、due to表语形容词under后接修、建中，of、from物、化分。

before、after表一点, ago、later表一段。

before能接完成时，ago过去极有限。

since以来during间，since时态多变换。

与之相比beside，除了last but one。

复不定for、找、价、原，对、给、段、去、为、作、赞。

快到、对、向towards，工、学、军、城、北、上、南。

but for否定用虚拟，复合介词待后言。

ing型由于鉴，除了除外与包合。

之后、关于、在......方面，有关介词须记全。

in内to外表位置，山、水、国界to在前。

如大体掌握如上介调用法口诀，就不易出错。

当然，至于介词的详尽用法，同形词又是连词及副词等内容此章不讲。

下面对该口诀分别举例帮助你理解消化。

早、午、晚要用in例：in the morning in the afternoon in the day in the eveningat黎明、午、夜、点与分例: at dawn, at daybreak at noon at night atmidnight 以上短语都不用冠词at ten thirty a.m.at six o'clock at 7：30 (seven thirty) at half past eleven at nine fifteen也可以写成seven to five 5点差7分(半小时以上) five minutes after two 2点过5分at a quarter to two 1点45分at the weekend 在周末年、月、年月、季节、周要用in。

但在某年某月某日则用on 例；in 1986in Aprilin December 1986 in July l983 in spring in the fist week of this semester阳光、灯、影、衣、冒in，即在阳光下，在灯下，在树阴下，穿衣、着装、冒雨等都要用in。

例：Don't read in dim light.They are sitting in the shade of a tree. a prisoner in ironsHe went in the rain to meet me at the station.The poor dressed (clothed) in rags in old society.以及：in the bright sunlight a merchant in disguise 乔装的商人the woman in white (black, red, yellow)in uniform in mourning 穿着丧服in brown shoes in his shirt将来时态in...以后例: They will come back in 10 days.We'll be back in no time.after... (从过去开始)小处at大处in例：I live in a great city (big city), my sister lives at a small town while my parents live at a village.有形with无形by，语言、单位、材料in例：The workers are paving a road with stone.The teacher is correcting the paper with a new pen."Taking Tiger Mountain by Strategy" is a good opera.I really can't express my idea in English freely in-deed．The length is measured in meter, kilometre, and centimetre.This board was cast in bronze not in gold.。

特征、方面与方式、心情、成语惯用in特征或状态：例: The Democratic Party was then in power. They found the patient in a coma.He has not been in good health for some years.Many who came in despair went away in hope. The house wasin ruins.The poor girl was in tears. Her clothes were in rags.His shoes were in holes.I only said it in fun.。

She spoke in grief rather than in anger.还有一些短语也用in，如：in jest 诙谐地，in joke 开玩笑地，in spite 恶意地，in fairness 公正地，in revenge 报复, in mercy 宽大，in sorrow 伤心地等。

His mind was in great confusion.Today everybody is in high spirits。

She and her classmates are in flower ages. The compaign was in full swing. 运动正值高潮中。

方面：例：They are never backward in giving their views. 他们从来不怕发表自己的意见。

A good teacher must be an example in study. 一个好的教师必须是学习的模范。

方式：例：All the speeches were taken down in shorthand.如下成语惯用in例如：in all 总计in advance 事前in the meantime 与此同时in place 适当地in hopes of(或in the hope of) 怀着.......希望in connectionwith 和……有关in contact with 和……联系in addition to 除......以外in case of 倘若，万一in conflict with 和......冲突in force 有效的，大批in depth 彻底地in regard to 关于in the neighborhood of 大约、邻近in retrospect 回顾，一想起in behalf of 为了帮助某人in the least 一点，丝毫in alarm 惊慌、担心in the opinion of 据……见解in the long run 从长远说来in a word 总之in one's opinion 在……看来in word 口头上in vain 无益地, 白白地in case 如果，万一，以防in detail 详细地in haste 急急忙忙地in conclusion 总之in spite of 尽管in other words... 换句话说in return 作为回报in doubt 怀疑in the name of 以...名义be confident in 对..有信心be interested in 对...感兴趣in love 恋爱中in debt 负债in fun (jest、joke) 玩笑地in hesitation 犹豫不决in wonder 在惊奇中in public (secret) 公开他(秘密地) in agood humour 心情(情绪)好"介词at、to表方向，攻击、位置、善、恶、分"。

介词at和to都可以表示方向; 用at表示方向时，侧重于攻击的目标，往往表示恶意；用to表示方向时，突出运动的位置或动作的对象，侧重表示善意。

试比较下列各句：A．She came at me. 她向我扑过来。

B．She came to me. 她向我走过来。

A．He shouted at the old man. 他大声喝斥那老人。

B. He shouted to the old man. 他大声向那老人说日子、日期、年月日，星期加上早午晚; 以下皆用on。

例: on Octorber the first 1949on May the first on the second of January 或on January the secondon a summer evening on Boxing Day on New Year's Day on my birthday但in the Christmas holidays; in the eighteenth century; in ancient times; in earlier times in modern times，at the present day当今on May Day on winter day on Decenber 12th 1950on Sunday 在星期天on Monday on Tuesday morning但last night 昨夜；in the evening 在晚上; on time准时，in time及时，等则不同。