In the study, 402 9th- and 10th-grade students from four New York City high schools in low-income areas were divided into three groups.

在研究中，402名来自纽约四所低收入地区高中的9年级和10年级的学生被分为三组。

youdao

It was discovered that rates of carbon cycling and growth rates among city trees were nearly four times faster than those in the countryside.

研究发现，城市树木的碳循环速度和生长速度几乎是乡村树木的四倍。

youdao

Air pollution in the city had reached four times the acceptable levels.

这座城市的空气污染程度曾高达可接受标准的四倍。

《牛津词典》

A city report says economic activity last year totaled almost three billion dollars, a four percent decrease from two thousand seven.

VOA: special.2009.03.30

They build these three large canals and this expands the area of the city by four times.

他们凿建了三条巨大的运河,使得城市面积扩大了四倍

耶鲁公开课 - 欧洲文明课程节选

Now,Shirley Griffith and Steve Ember tell us all about Cape May as the city celebrates its four hundredth anniversary this year.

VOA: special.2009.06.01

Mayor Michael Bloomberg, a billionaire with no prior government experience, took over New York City four months after September 11.

CNN: 10 Questions For Michael Bloomberg

Weiss joined City four years ago and has played four games this season - three in the Carling Cup, including a goalscoring appearance against Arsenal, and one in the FA Cup.

BBC: Bolton complete deals for Weiss and Holden

About four hours north of New York City on four remote acres sits a stealth Saranac home for sale that is truly unlike any other.

FORBES: Shhh...Spy-Worthy Homes for Sale