Keep a close watch on the enemy's movements.

密切注意敌人动向。

《新英汉大辞典》

youdao

Some use them to keep a close watch on the demand for their line of work or gather information on compensation to arm themselves when negotiating for a raise.

有些人用它来密切关注自己所在行业的需求情况，或者收集有关薪酬的信息，以便在加薪谈判时为自己做好准备。

youdao

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 government said that it would continue to keep a watch on the currency's movements and "respond as appropriate".

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The rest are in the 10% to 13% range, so keep a watch on them, since they may become buys long before the next issue of Income Securities Investor.

FORBES: Magazine Article

In many cases fellow inmates are instructed by their jailors to keep a watch on such prisoners, I am told, and guards are posted outside the cell, which may also be under CCTV coverage.

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