Immigration【n.】

1. the process of coming to live permanently in a country that is not your own移民，移居

The country has seen a large increase in immigration over the past decade.

过去十年里，这个国家的移民数量大幅增加。

2. the department of government that deals with people who come to live in a country移民局

She works for immigration at the airport.

她在机场的移民局工作。

—> migration【n.】

1. the movement of people/animals from one country or region to another in order to settle there（人或动物的）移居，迁移

The migration from rural areas to cities has increased in recent years.

近年来，从农村地区向城市的迁移有所增加。

The migration of birds is a fascinating natural phenomenon.

鸟类的迁徙是一种令人着迷的自然现象。

2. the process of changing from one computer system to another, or of moving data from one system to another（计算机系统或数据的）迁移

The company is planning a migration to a new software platform next month.

该公司计划在下个月迁移到一个新的软件平台。

—> emigration【n.】

1. the act of leaving one's own country to settle permanently in another移居外国；移民

Emigration from the country has increased due to economic difficulties.

由于经济困难，该国的移民人数增加了。