The average age at that time was twenty-one.

Olympic Movements and International Political Development of Twenty-one Century

奥林匹克运动与21世纪初国际政治发展

Development Tendency of Building Structure Design and Construction Technologies in Twenty-one Century

廿一世纪建筑结构设计和建造技术的发展动向

Twenty-one century Zhujiang delta urban gang total urban planning research

21世纪珠三角城市群总体城市规划研究

Opportunity and challenge: sustainable development of China in twenty-one century

机遇与挑战：21世纪中国可持续发展的取向

We waited twenty-one years, don't fail us now.

我们等了21年了，如今不要让我们失望。

On each of the factors were fine research, twenty-one indexes were obtained.

对每个因素进行精细化研究，共得出二十一个指标。

Twenty-one members of the South African rugby team were isolation as they are believed to have been in close contact with the case on their flight, said Kagoshima city, which is hosting the team.

东道主鹿儿岛市称，南非橄榄球队的21名队员被隔离，因为据信他们在飞行途中与感染病例有密切接触。

How many famous buildings are there in this country? Twenty-one.

这个国家有几栋著名的建筑物？21栋。

The Public Opinion about Twenty-one Treaties between China and Japan in 1915

1915年中日二十一条交涉的社会舆论

Be one of the main method for ceramic materials in the twenty-one century.

陶瓷材料的固溶强化将成为21世纪提高材料性能的主要方法之一。

The diet is chosen under a franchise that is universal for citizens aged twenty-one and over.

国会由年满二十一岁以上的公民普遍选举产生。

Twenty-one people were killed and four others missing as heavy rain lashed in the township, according to the announcement.

当地政府8月13日通报，8月11日至12日，湖北省随县柳林镇发生极端强降雨天气，已造成柳林镇8000余人受灾，21人死亡、4人失联。

Twenty-one patients received a placebo plus standard treatment.

21位患者在标准疗法的基础上服用了安慰剂。

Nanotechnology is one of the three high technologies in the twenty-one century.

纳米科技是21世纪的三大科技之一。

He said he was twenty-one years old and the employment agency took him on faith.

他说他21岁，职业介绍所毫不怀疑就相信了他。

The researchers tested the blood of all twenty-one people.

研究人员给所有参加测试的21名人员检查了血液。

This paper reports twenty-one normal results in 13 transplant renal allografts.

本文报道了13例移植肾进行的21次正常检查结果。

There are fifteen books on the first shelf, twenty-one on the second, that makes thirty-six in all.

书架的第一层有15本书，第二层有21本，总共是36本。

According to a scientific research, forming a habit takes twenty-one days.

一项科学调查显示，养成好的习惯需要用21天的时间。

A class of fifth system with one twenty-one order singularity

一类有21阶奇点的五次系统