1. There has been a migration of people from the country to the towns.
    人们从乡下移居城镇。

2. Scientists have studied the migration of fish over long distances in the river.
    科学家研究过江中的鱼类远距离回游的现象。

1. migration

1. 移行：因此,研究者推测,NMDA异常将导致神经元移行(migration)、突触连接减少、神经元变性和凋亡. 越来越多的证据提示,非典型抗精神病药物治疗精神分裂症的基础与其逆转NMDA功能低下有关. 精神分裂症尸脑证明,前额叶和丘脑的NMDA受体密度和数量明显低于正常人.

2. migration的反义词

2. 迁徙：最新诗集<迁徙>>(Migration)的获奖应该是众望所归,毕竟几十年来国家图书奖对他已经亏欠良多. 珍妮.伯兹奥尔的处女作<烛芯>>(ThePender-wicks)毫无争议地捧得青年文学奖. 该作品讲述了一个单身父亲和4个女儿之间的故事.

1. the movement of persons from one country or locality to another

2. the periodic passage of groups of animals (especially birds or fishes) from one region to another for feeding or breeding

3. (chemistry) the nonrandom movement of an atom or radical from one place to another within a molecule

4. a group of people migrating together (especially in some given time period)