（1）call on拜访某人，号召
We will call on Mr．Li tomorrow．
We are called on to help those in trouble．
（2）call at拜访某地
I called at your office yesterday,
（3）call for需要；要求；邀约(人)；取(物)
Success called for hard work．
call for a doctor去请医生
（4）call in 请来；收回
Mother is badly i11．so call in a doctor at once．
（5）call up打电话；征召；使回想起，使回忆起
I called Tom up and told him the news．
In most countries men are called up at the age of 18．
（6）call out大声叫喊，大声说出；
（7）call off 取消、停止