引用其他来源的资料要放在引号里。

If you take text from other sources, place it in quotes.

《牛津词典》

请注意双引号的使用，它确保了原始命令中引用的参数被保留并得到正确识别。

Note the use of double quotes, which ensures that quoted arguments in the original are retained and identified properly.

youdao

\ 9用来引用已获取的子模式，在这个例子中，变量\ 1就保存着第一个匹配的引号。

\ 9 hold references to previously captured subpatterns. The first matched quote, in this case, will be held by the variable \ 1.

youdao