种族界限

例句：

1. 1. The government'spolicy on race relations has been a sourceof controversy for years.
   政府在种族关系方面的政策多年来一直是争议的焦点。
2. 2. Thecountry's strict immigration laws have createdsignificant racial boundaries between different ethnic groups.
   该国严格的移民法律已经在不同民族群体之间建立了显著的种族界限。
3. 3. Racial discrimination is a fundamentalproblem that needs to be addressedin order to promote equality and harmony.
   种族歧视是根本问题，需要解决以促进平等和和谐。