When cold weather comes ,many bird move to _warm_places to find food .Some fishes give birth in warm water and move to _cold_water to feed .The __famous__migration is_probabe_the migration of the fish_ called_'salmon",this fish is bom in _ fresh_wath but it travels__many miles to salty water.There it spends _ its_ life .When it is cold ,it returns to its birth place in fresh water ,Then it gives birth and dies there
当寒冷季节来临时,许多鸟类会迁徙到温暖的地方觅食.有些鱼类在温暖的水域产子而在冷水中喂养.最著名的迁徙也许是被称为鲑鱼(大马哈鱼）的迁徙,这种鱼生在淡水中却要游到数英里外的咸水中,在那里度过一生,当天气转凉,它又洄游到淡水中,然后产子并在那里死去.