Most astronomers believe that the large concentration of mass at the galaxy's center is a black hole whose gravity is causing the gas to whirl.

大多数天文学家认为，星系中心的大量物质是一个黑洞，它的引力导致气体旋转。

youdao

Is the national economy, transportation, cultural centers, is also an important industrial center for the world's largest concentration of jute.

是全国经济、交通、文化中心之一，也是重要的工业中心，为世界最大的黄麻集中地。

youdao

We in the 21st century, when the urbanization should consider these new factors, avoid to the center city population concentration and detours.

我们在21世纪推进城市化的时候，是否应该考虑这些新因素，避免人口过度向中心城市集中而走弯路。

youdao

Csizsik-Csatary participated in the deportation of 15, 700 Jews to the Auschwitz concentration camp in 1944, witnesses have told the center.

CNN: Nazi war crimes suspect arrested in Hungary

Laszlo Csizsik-Csatary is accused of sending more than 15, 000 Jews to the Auschwitz concentration camp in the spring of 1944, the Simon Wiesenthal Center said.

CNN: Nazi war crimes suspect arrested in Hungary

Early findings from a 2007 Wake Forest University Baptist Medical Center study indicate that regularly practicing tasks that necessitate shutting out distractions can help healthy older adults improve their concentration.

FORBES: Magazine Article