it

它、牠指事物或动物

I bought a new phone, but I dropped it the next day.

我买了一支新手机，隔天就把它摔了。

不译虚主词，指天气、时间、距离等

It's raining hard, so take an umbrella with you.

雨下得很大，出门记得带伞。

这形式主词或形式受词

It is clear that they need more time to finish.

很明显，他们需要更多时间才能完成。

正是用于强调句

It was my sister who suggested the whole trip.

提议这整趟旅行的正是我姊姊。

情况、状况指整体情势

How's it going at the new school?

你在新学校的情况还好吗？

他、她指婴儿或性别不明者

The baby was crying because it was hungry.

宝宝饿了，所以一直在哭。

鬼游戏用语

You're it, so close your eyes and start counting.

你当鬼，闭上眼睛开始数。

资讯科技、资讯技术缩写，常大写

She works in IT for a large insurance company.

她在一家大型保险公司负责资讯科技的工作。