第二十一的英文怎么写的

twenty-first num. 第二十一.

例句

Welcome to the twenty-first century.

欢迎进入21世纪。

What defines a twenty-first-century entrepreneur?

21世纪创业者的特征有哪些？

But in the twenty-first century, a very different story is unfolding.

但在21世纪，呈现在大家面前的又是另外一种故事。

The twenty-first century began with a very unequal distribution of power resources.

21世纪初，权力资源分布相当失衡。

Seventeen civilians were hurt. Most are students who had been attending a twenty-first birthday party.

17名平民受了伤，其中大多数是参加一个21岁生日聚会的学生。

Geothermal energy probably will not make large-scale contributions to the world energy budget until well into the twenty-first century, if ever.

在进入21世纪之前，地热能可能不会对世界能源预算作出大规模贡献。