What does call in mean? It it a phrasal verb and an idiom?

[ElGatos]

English Grammar Error, Intermediate level

ESL/EFL Test #11 "I really wonder", question 7

If we have the times, I promise you that we'll do the best we can to call in to see you next time we're in town.

(a) times
(b) we'll do
(c) call in
(d) in town

English Grammar Error, Intermediate level

ESL/EFL Test #11 "I really wonder", answer 7

If we have the time, I promise you that we'll do the best we can to call in to see you next time we're in town.

Correct entry: time
The error was: (a) times
_________________________

should be - time also not call in but call ahead.

ElGatos

[Mister Micawber]

.
No, 'call in' is fine-- it means 'visit briefly'.
.
_________________
Native English teacher at Mister Micawber's