by 什么时候用?例子by 什么时候用?请举例子?by 就是延伸by前面的内容是吗?共3个问号,谢谢

by 什么时候用?例子
by 什么时候用?请举例子?
by 就是延伸by前面的内容是吗?
共3个问号,谢谢

第一,二问：我给搜索了一下,下边这个比较全了,高中水平的.
第三问：如下,很显然不全是.你说的应该是被动语态中表示动作的实施者.
介词by的用法归纳
河北省鸡泽县第一中学 胡贺军 057350
介词by可以用来表示方位、时间、手段等,其用法在高考中曾多次出现.下面结合高考试卷和其它一些例句做一下归纳：
一、by+地点名词.表方位,意为：“在…旁边”.如：by the lake/river/tree/window/door等.
She searched the top of the hill and stopped to rest on a big rock by the side of the path.(NMET90)她搜索了山顶,然后停下来在路边的一块大石头上休息.
After supper she would sit down by the fire,sometimes for as long as an hour,thinking of her young and happy days.(2003上海·春）晚饭后,她常坐在火旁,有时长达一个小时地回忆她那青春、快乐的年代.
注：有时可表:“从…旁经过”,多与动词go/walk/pass等连用.
As we boys were rushing towards the playground,Jim slipped by the table.(NMET92完形）当我们这些男生冲向操场时,吉姆从桌旁溜过.
二、by+时间名词.意为：“到…时（已发生某事）,此时谓语多用完成时；最晚、不迟于…,在…之前”.如：by now/then/this time/next Friday/the end of/three o`clock等.
By the end of last year,another new gymnasium had been completed.(2003上海·春）到去年年底,又有一座新体育馆峻工了.
The train leaves at 6:00 pm.So I have to be at the station by 5:40 pm at the latest.(NMET97)火车下午六点开,所以最晚我得五点四十赶到车站.
三、by+名词.可用来表方法、方式、手段等.
1、by+the+可数的时间、长度、重量等名词.意为：“按…计算,按…买(卖)”.如：by the pound/ton/yard/meter/dozen/bale/day/month等.
Cleaning women in big cities usually get paid by the hour.(NMET98)城市里的女清洁工通常按小时获得报酬.
In the market,tobacco is sold by the bale,eggs by the dozen and salt by the pound.在市场里,烟叶按捆卖,鸡蛋按打卖,盐按磅卖.
2、by+表示时间、长度、重量等总称的不可数名词（名词前不加冠词）.意为：“按…计算,按…买(卖)”.如：by time/volume/length/weight/height/depth/width/area等.
As we all know,the freight of the luggage is charged by weight.众所周知,行李的运费是按重量计算的.
3、by+交通工具、交通方式名词（名词前不加冠词,不变复数）.意为：“通过…,由…,乘…”.如by train/rail/tube/taxi/bus/truck/bike/boat/plane;by land/road/sea/water/air等.（on foot)
It takes a long time to go there by train;it`s quicker by road.(或by bus)(NMET93)乘火车去那儿要花很长时间,公路比较快.
“I usually go there by train”.“Why not try going by boat(或water)for a change?”(NMET92)“我常乘火车去那儿.”“为何不尝试一下坐船呢?”
4、by+抽象名词或具有抽象意义的普通名词（名词前不加冠词,不变复数）.意为：“靠…,通过…,由…所致”.如：by skill/determination/practice/diligence/inference/chance/accident;by mail/letter/radio/fax/telephone/telegraph/hand/machine等.
Although he had been searching in the wrong area most of the time,he found it by logic,not by luck.(NMET2002阅读）虽然他曾大部分时间一直在错误的地方寻找,但他还是靠逻辑推理而非运气,找到了它.
I made a coat with my own hands.It was made by hand,not by machine. 我用双手织了一件外套.它是用手工织的,而不是机器织的.
5、by+ 地点或工具等具体名词.表路线、途径,意为：“通过（某物、某地）,取道…”.如:by a stone bridge/the back door/the freeway/country roads等.
The man entered the room by the back door.那人通过后门进入了房间.
6、by+动词—ing.意为：“通过…,靠…,凭…”.如：by waiting/practing/begging/working/imitating等.
He gained his wealth by printing works of famous writers.(NMET95)他通过印刷著名作家的作品而获得了巨大的财富.
Our bodies are strengthened by taking exercise. Similarly,our minds are developed by learning.(2000上海)身体是靠锻炼强壮的,同样,大脑是靠学习开发的.
四、by+数量词.
1、表升降、增减的程度.如：by one-fifth/20 percent/￡3/two feet等.
With production up by 60%,the company has had another excellent year.(NMET2000)产量上升了百分之六十,这家公司今年的业绩极好.
The demand for organic food is increasing by about one third every year.(NMET2002阅读)对绿色食品的需求每年在增长大约三分之一.
2、表示距离和面积、体积中的尺寸及乘除法中的运算.如：by 2cm/6 inches/four feet/nine yards/a hair`s breadth等.
Luckily,the bullet narrowly missed the captain by an inch.(2002上海）幸运地是,那颗子弹差一英寸就击中了上尉.
The bed is three meters wide by two meters long,and can fit at least four at one time.(NMET2001阅读)那张床三米宽,两米长,一次至少可以睡四个人.
五、by+身体部位名词或衣服名词.表示被抓住身体/衣物的某一部分,常与动词catch/seize/take/hold/grab等连用.如：by the hair/hand/arm/nose/horns;by the collar/lape/sleeve等.
The policeman caught the thief by the arm.警察抓住了小偷的胳膊.
The soldier grabbed the child by the collar.那个士兵揪住了孩子的衣领.
六、by的常见短语：
by means of/by way of/by the way/one by one/step by step/side by side/shoulder by shoulder/by oneself/by birth/by society/take…by surprise/learn…by heart/what do you mean by …/by my watch等.