前言

That book has a preface, not a foreword.

那本书有序文, 没有言。

The preface is complete in itself.

这言本身就是完整。

He gave a rather disjointed account of his experience in the jungle.

"在谈到他在热带丛林里经历时,他言不对后语。"

The introduction is mainly about the definition of eponym, and emphasizing its development and synchrony with language.

言要是名祖名词，述名祖名词发展和存在现状，并强调了名祖名词始终与语言发展共时。