come back to earth with a bang

Từ điển Oxford Advanced Learner 8th

come back/down to ˈearth (with a ˈbang/ˈbump) | bring sb (back) down to ˈearth (with a ˈbang/ˈbump) idiom
(informal)to return, or to make sb return, to a normal way of thinking or behaving after a time when they have been very excited, not very practical, etc.
see also ↑down to earth
Main entry: ↑earth_idiom