call on

US /kɔːl ɑːn/
UK /kɔːl ɑːn/
"call on" picture
1.

请, 呼吁

to ask someone in a formal way to do something

:
The teacher decided to call on a student to answer the question.
老师决定一位学生回答问题。
The president will call on the nation to unite during this crisis.
总统将呼吁全国在此危机期间团结起来。
2.

拜访, 看望

to pay a brief visit to someone

:
I decided to call on my grandmother after work.
我决定下班后拜访我的祖母。
We should call on our neighbors to see if they need anything.
我们应该拜访我们的邻居,看看他们是否需要什么。