U.S. officials have been keeping close watch on the situation.

美国官员们一直密切关注着事态的发展。

《柯林斯英汉双解大词典》

The police are keeping a close watch on the suspect's movements.

警察正在密切监视嫌疑犯的活动。

《牛津词典》

The government is keeping a close watch on how the situation develops.

政府正在密切注视着形势的发展。

《牛津词典》

The Environmental Protection Agency, is keeping a close watch on threats to the delicate eco-system along the coastline.

VOA: standard.2010.05.18

Well,I think it's that governments around the Gulf do actually keep a very close watch on their populations and on people coming in and out of their countries.

VOA: standard.2010.08.11

"The virus is spreading under a close and careful watch,".

VOA: standard.2009.12.25

But are signs effective at reminding distracted parents to keep a close watch on their children?

FORBES: Do Deadly Distractions Lead To Drowning? - Parents Question Cruise Line Policy As Boy Remains In Coma

Montreal referee Yves Lavigne then moved over to keep a close watch on the challenger.

NPR: St-Pierre Manhandles Diaz At UFC 158

The daughter of founder Dave Thomas is keeping a close watch on this year's round of 16.

WSJ: BracketRacket: Jim Boeheim, R.L. Stine and pizza