keep an eye on
US /kiːp ən aɪ ɑn/
UK /kiːp ən aɪ ɑn/

1.
照看, 留意
to watch someone or something carefully
:
•
Can you keep an eye on my luggage while I get a coffee?
我买咖啡的时候,你能帮我照看一下行李吗?
•
The teacher asked the students to keep an eye on the clock during the exam.
老师要求学生在考试期间注意时间。