Ответ:

1 The concert was called off because of epidemic situation.

2 The doctor called on my granny yesterday to see if she needs the injection.

3 Jack and Sue called in last week to have a barbeque with us.

4 The flood called for immediate action.

Объяснение:

call off - отменять

call on - посещать, навещать

call in - приходить в гости

call for - требовать (действий), предполагать необходимость