immigration/migrate/immigrate/emigrate/emigration
记忆：
1. migrate [ mai5^reit, 5mai^reit ] To move from one region and settle in another. vi. 移动, 移往, (鸟类的)迁徙 vt. 使移居, 使移植 Some birds migrate to find warmer places. 一些鸟迁徙寻找暖和的地方。
2. immigrate [ 5imi^reit ] To enter and settle in a country or region to which one is not native. im, 即in, 里面；immigrate vt. 使移居入境 vi. 移来 The promise of prosperity in the United States encouraged many people to immigrate. 美国繁荣的前景鼓励着很多人移居入境。
3. immigration [ 7imi5^reiFEn ] n. 外来的移民, 移居入境 The immigration increased the population of the country. 移民增加了国家的人口。
4. emigrate [ 5emi^reit ] To leave one country or region to settle in another e-, 外面，emigrate vi. 永久(使)移居 vt. (使)移民 After the Nazis came to power in Germany, many scientists emigrated 在德国在纳粹上台掌权后，许多科学家移民出去了。
5. emigration [ 7emi5^reiFEn ] n. 移民出境, 侨居 The emigration decreased the population of the country. 移民减少了国家的人口。
另类阅读：
In history people migrated. When the surroundings were poor, they would emigrate; when the conditions were better than where they lived, they would immigrate. The emigration and immigration would affect those places a great deal.