migrate

动词 migrate:

1. move from one country or region to another and settle there
   同义词：transmigrate
2. move periodically or seasonally

1. To all appearance, Mr. Li is going to migrate.
   李先生显然是要移民了。
2. In winter many of our birds migrate form here to warmer countries.
   我们有许多鸟儿冬天从这里迁移到比较温暖的国家去。
3. In some developing countries more and more people migrate to urban area.
   在某些发展中的国家，越来越多的人向市区迁移。
4. Some tribes migrate with their cattle in search of fresh grass.
   有些部落为了寻找新鲜的牧草而带着他们的牲畜迁移。

mi.grate

v.intr.（不及物动词）
mi.grat.ed,mi.grat.ing,mi.grates
To move from one country or region and settle in another.
移居，迁徙：从一个国家或地区迁移到另一个国家或地区定居
To change location periodically, especially by moving seasonally from one region to another.
迁移，移栖：定期变换所在地，尤指季节性地从一地迁移到另一地

来源：
Latin migr3re migr3t- * see mei-
拉丁语 migr3re migr3t- *参见 mei-

【引伸】
mi.gra.tor
n.（名词）
Migrate, which is used of people and animals, sometimes implies a lack of permanent settlement,especially as a result of seasonal or periodic movement.Emigrate and immigrate are used only of people and imply a permanent move,generally across a political boundary.Emigrate describes the move relative to the point of departure:
Migrate 用于人和动物， 有时含有缺乏永久的居住地之意，尤指出于季节性或定期迁移这两个原因。Emigrate 和 immigrate 仅用来指人， 意味着永久性的迁移，一般指越过政治意义上的疆界。Emigrate 的含义与离开有关：
例句：
After the Nazis came to power in Germany, many scientists emigrated (that is, left Germany).
纳粹夺取了德国的政权之后，许多科学家都迁走了（也就是说，离开了德国）。

By contrast,immigrate describes the move relative to the destination:
与之相对，immigrate 指的是与到达目的有关的移动：
例句：
The promise of prosperity in the United States encouraged many people to immigrate (that is, move to the United States).
兴旺发达的前景吸引了众多的移民到美国（也就是指，迁入了美国）