The most recent large-scale wave of immigration has produced only first- or second-generation Americans. 然而从最近一次大规模移民潮至今,还只有第一和第二代移民。
By increasing the supply of skilled workers, such immigration would also reduce the widened earnings gap between more and less skilled workers. 由于增加了技术人才的供应,此种移民潮又可以拉近因技能原因造成的劳动力之间的收入差距。