at, in , on, 和 by 表示时间的区别：at 指时间表示：1）时间的一点，一时刻：They come home at surprise (at noon, at midnight, at ten oclock, at daybreak, at dawn).2) 较短的一段时间。可指某个节日或认为一年中标志大事的日子。His grandfather died at seventy-two.At the beginning (middle, end) of that month he was sick.He went home at Christmas (at New Year, at the spring Festival, at night, at midsummer).In 指时间表示：1）在某个较长的时间（如世纪，朝代，年，月，季节，及泛指的上午，下午和晚上等）内。He died in the holidays. He was born in 1942.2) 在一段时间之后。He will come round in a day or two.I will finish it in three hours.On 指时间表示：1）具体的时日和一个特定的时间，如某日，某节日，星期几等。He will come to meet us on our arrival.On May 4th (On Sunday, On New Years day, On Christmas Day), there will be a celebration.2) 在某个特定的早晨，下午或晚上。He arrived at 10 oclock on the night of the 5th.He died on the eve of victory.3) 准时，按时。If the rain should be on time, I should reach home before dark.表示地点的区别In 表示地点1) In 表示比较大的地方，2) 虽然是很小的地方，如果说话人住在那里，也可用in.商店，机关，学校等，若看作一个地点（point)用 at,若看作一个场所（place)用in.I met him at the post-office.Im now working in the post-office.On 表示地点，一般指与面或线接触：1）“在上面”He put the book on the table and sat on the chair.The picture was hanging on the wall.2) “在 旁边”New work is on the Hudson River.Xiamen is on the river.He lives in a house on the river.1). near, by, beside, at 表示“在 附近”的区别：near 表示相对的“近”，实际距离可能还很远。例如：There is a post office near our school.Suzhou is near Shanghai.By 和 beside 都表示“靠近”，实际距离不可能很远，但 beside 比 by 更具体的表示出“在 旁边”的意思。例如：There is a big tree by the river.He was sitting beside her.by 还可以表示 “尺寸，距离”。例如：They escaped death by inches.Do you see the hole high up in the wall, about 18 cm by 9?常用短语在英语中介词的使用频率比较高，而介词 in, on 和 at 又是介词中使用频率比较高的词，收集了介词 in, on 和 at 表示时间，地点和状态的常见的短语, 请注意一些短语用不同的介词，意义不同，有些区别不大。表示时间:in 表示时间 in 1999, in 20 century, in a flash(瞬时), in a lucky hour(在幸运时刻), in a minute, in a second, in a short time, in a while, in a wink(一瞬间) in advance(预先),in an emergency(在紧急地时候), in an evil hour(在不幸地时刻 ), in an instant, in ancient times, in broad day(在大白天), in course of, (在 期间), in December, in due course(及时地), in future, in good season(及时地), in no time(马上), in ones childhood, in ones spare time, in ones teens, in ones youth, in recent years, in season(适时), in seconds(在很短的时间 ), in some cases(有时候), in spring, in the afternoon, in the beginning, in the daytime, in the end, in the evening, in the future, in the long run(最后), in the meantime, in the morning, in the nick of time(在紧急关头), in the night, in the past, in the thick of (在最激烈的时刻 ), in the thick of(在最激烈的时刻), in this period, in those days, in time of war, in time， on 表示时间 on a certain day, on a sudden(突然), on a winter morning, on Christmas Day, on night shift, on ones birthday, on schedule(按时), on Sunday, on that date, on the eve of, on the following day, on the instant(马上), on the moment(立刻), on the Monday morning, on the New Years Eve, on the next morning, on the point of(正在 时候), on the spur of the moment(立刻) on this day, on this occasion, on time, at 表示时间 at a time(在某时), at a wedding(婚礼), at all times(一直), at any moment, at any time, at Christmas, at dark (天黑时), at dawn(在黎明), at daybreak, at dinner-time, at dusk(在黄昏 ), at Easter, at first sight,(一见到 ), at first, at last, at midnight, at night, at nightfall, at noon, at present, at six clock, at sunrise, at sunset, at that moment, at that time, at the age of, at the beginning of , at the correct time, at the end of, at the last minute, at the moment, at the present stage at the same time, at the stage(眼下) at the start, at the time being, at the time of, at the very start, at this point(此时 ), at this season, at this time of day, at times(有时） 表示地点in 表示地点 in a car, in a queue, in advance of (在 前面), in all the direction, in appearance, in corners(在角落里) in doors, in front (of), in good light(在光线好的地方), in heaven, in place(position)(在适当地位置), in places(处处 ), in port(在港内), in public places, in shore(靠岸), in society, in the air(在空中) in the bank, in the book(书的内容里), in the centre(在中央), in the countryside, in the distance(在远处那边), in the east of(在 东部) in the east, in the fields, in the film, in the front rank(在前列), in the front row, in the lab, in the letter(信的内容), in the middle of, in the moonlight, in the newspaper(报纸的内容里 ), in the open air(在户外), in the open(在野外), in the picture, in the rain, in the room, in the shade of, in the sky, in the suburbs of, in the sunshine, in the tree, in the universe, in the vicinity of(在附近), in the warm(在暖和的地方) in the world, in(on) the bus, in(on) the street, on board (在船上) on camera(出现在电视上), on campus, on deck(在甲板上), on earth, on 表示地点 on high(在高处), on land, on the bank, on the beach, on the borders, on the ceiling, on the coast, on the committee, on the corner(在拐角处), on the east of(在 的东面) on the farm, on the first floor, on the football field, on the (play)ground, on the horizon, on the island, on the left/right,. on the market, on the page 12, on the railway line, on the river, on the road, on the roof, on the sea, on the shore, on the side