an introduction at the beginning of a book explaining its purpose, thanking people who helped the author, etc.

In his preface, the author says that he took eight years to write the book. 在前言中，作者说他写这本书用了8年。

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.

If you preface your words or actions with something else, you say or do this other thing first.

Each work is prefaced by a descriptive note and concludes with an author's note. 每一作品都以说明性文字作开端，以作者自己的批注为结尾。

I should like to preface my response with the following observation. 我想以以下评论作为我回应的开头。