markdown区块引言怎么设置

Markdown使用email形式的区块引言，如果你很熟悉如何在email信件中引言，你就知道怎么在Markdown文件中建立一个区块引言，那会看起来像是你强迫断行，然后在每行的最前面加上>：

> This is a blockquote with two paragraphs. Lorem ipsum dolor sit amet,
> consectetuer adipiscing elit. Aliquam hendrerit mi posuere lectus.
> Vestibulum enim wisi, viverra nec, fringilla in, laoreet vitae, risus.
> 
> Donec sit amet nisl. Aliquam semper ipsum sit amet velit. Suspendisse
> id sem consectetuer libero luctus adipiscing.

Markdown也允许你只在整个段落的第一行最前面加上>：

> This is a blockquote with two paragraphs. Lorem ipsum dolor sit amet,
consectetuer adipiscing elit. Aliquam hendrerit mi posuere lectus.
Vestibulum enim wisi, viverra nec, fringilla in, laoreet vitae, risus.

> Donec sit amet nisl. Aliquam semper ipsum sit amet velit. Suspendisse
id sem consectetuer libero luctus adipiscing.

区块引言可以有阶层（例如：引言内的引言），只要根据层数加上不同数量的>：

> This is the first level of quoting.
>
> > This is nested blockquote.
>
> Back to the first level.

引言的区块内也可以使用其他的Markdown语法，包括标题、清单、程式码区块等：

> ## This is a header.
> 
> 1.   This is the first list item.
> 2.   This is the second list item.
> 
> Here's some example code:
> 
>     return shell_exec("echo $input | $markdown_script");

任何标准的文字编辑器都能简单地建立email样式的引言，例如BBEdit，你可以选取文字后然后从选单中选择增加引言阶层。