keep a watch on
美
英 
例句
"But to do that, " Nancy pointed out, "You'd have to keep a watch on him all the time. "
“但要做到这一点,”南希指出,“你们就得整天监视着他。”
She said all must keep a watch on the election process.
她说所有人必须对选举过程进行监督。
The Royal suites offer the option of a live webcam that the owners can access and keep a watch on their pet.
总统套房可以提供网络摄像头以便主人进入房间和照看他们的宠物。