call for在表示“号召”意思时，侧重于“要求”，后边常常直接跟名词。call for还有去接(某人)，去取(某物)和需要的意思。call on有“号召”的意思，后边可以跟什么人做什么事情，call for后边常常跟表示事物的名词，而call on后边常常跟表人的名词。
1．Call at (1)访问（某处）；（2）（车船等）停靠（某地）。
We called at Mr.Smith yesterday.昨天我们拜访了史密斯先生家。
The train calls at every station.火车每站必停。
2．Call back (1)回电话；（2）召回，叫回来
The boy had gone but a few steps,when his father called him back.孩子才走几步，父亲就把他叫了回来。
I’ll call you back in half an hour.半小时后我会给你打电话的。
3．Call for (1)需要，要求（有……）。（2）去取（sth.）,去接（某人同往某处）
He’ll call for the mail on his way home.在回家的路上他要去取邮件。
I’ll call for you at 6 o’clock and we’ll go to the theatre together.
The occasion calls for quick action.情况需要采取紧急行动。
4．Call in 找来；请来
As the child’s condition grew worse,the parents called in a doctor.由于孩子的病情恶化，他父亲请来了一位医生。
5．Call on (1)访问（sb.）,(2)号召；要求
I called on the director at his office.我到主任的办公室找他。
The Party calls on us to study hard. 党号召我们刻苦学习。
6．Call up (1)打电话 (2)使人想起
On reaching there,I’ll call you up.一到那里，我就会给你打电话的。
The picture calls up scenes of my childhood.这张相片是我想起了童年的情景
7.call off 取消
The meeting has been called off. 会议已经取消。
Why was the football match called off? 足球赛为什么取消?
