种族分界线

例句：

1. 1. The scientist studied the behavior of different races of monkeys.
   这位科学家研究了不同种族的猴子的行为。
2. 2. The book explores the history and culture of different races around the world.
   这本书探讨了世界各地不同种族的历史和文化。
3. 3. The politician is known for his support of multiculturalism and equality among races.
   这位政治家因其对多元文化和种族平等的支持而闻名。