介词in的基本意思是:“在……以内”，可以表示“时间以内”，“地点以内” ，表示“ 方式”时，常译作“采用，以”，但是本质上所指的也是“在……之内”，比如，用英语(in English)就是在英语的氛围里 。

1.作状语

A railway link to Amsterdam in 1847 attracted rich traders from many regions.

在1874年，连接阿姆斯特丹的铁路线吸引了来自很多地区的有钱商人。

The princess had been invited to ride in a chatity race.

公主被邀请在一场慈善赛马比赛中骑马。

Alf offered her a role in the play he was directing.

阿尔夫在他导演的戏中给她安排了一个角色。

A coin is put in a dumpling, which signifies good luck in the coming year for the person who eats it.

在饺子里面包上硬币，预示着吃到这个饺子的人来年好运。

A good neighbor is also one who likes to help out in small ways.

好邻居就是喜欢以各种各样方式帮助解决困难。

2.作定语

A friend in need is a friend indeed.

患难见真情。(一个在困难中的朋友才是真朋友。)

We met three women in black.

我们碰见三个穿着黑衣的女子。(就是人在衣服里面)

The light in the window went out.

窗户里的灯熄了。

3.作表语

He was is his car.

他坐在他的车里。

4.作补语

He found himself in the forest, not knowing where to go.

他发现他自己在森林里，不知道往哪里走。