…的序幕(或前奏)
an event that comes before something more important
We're hoping these talks could be a preface to peace. 我们希望这些会谈能拉开和平的序幕。
People often deny prejudice as a preface to saying something racist.
Naval ships circled the island as a preface to invasion.
These remarks served as a preface to his announcement that he was leaving the firm.
He used to sling an arm around my shoulder as a preface to asking a particularly awkward question.
See also: preface noun