Twenty percent of us exercise only one to three times a week.

百分之二十的人一周只锻炼一到三次。

youdao

In Belgrade, the mood is bleak. Serbs have tasted defeat many times over the past twenty years, during the slow and painful dismemberment of Yugoslavia, but few moments will hurt as much as this one.

而在贝尔格莱德则是一片萧瑟的气氛，经历过漫长而痛苦的前南解体，塞尔维亚人近二十年来屡尝败果，但这次的打击真是太大了。

youdao

Yes, Monsieur, one and twenty years ago; and since then we have not seen the poor marquis three times.

是的，先生，那是二十一年以前的事了，从那以后，我们见到可怜的侯爵总共不过三次。

youdao

Mister Sumrall says NASA estimates the new Ares One will be twenty to thirty times safer than the Space Shuttle.

VOA: special.2009.12.30

The book entered The New York Times Best Sellers list at the number one position on September twenty-fifth.

VOA: special.2009.10.09

The last one,by astronaut Gordon Cooper, circled the Earth twenty-one times.

VOA: special.2009.06.17

It is called "gigabit Ethernet, " and is able to send data at one billion bits per second, over twenty times faster than a T3 line.

FORBES: Weaving The Perfect Net

On Monday, November 26, the shipping lead times for the iPhone 5 in twenty-one of the twenty-three countries I checked had decreased from two weeks to one week.

FORBES: Apple's iPhone 5 Web Site Lead Times Down to 1 Week

This is the sustainability challenge of the twenty-first century and thus one of the governance challenges of our times as well.

UN: Secretary-General