擅长:python、mysql、java
<p>问题是你也在替换角色。您需要在regex中使用<strong>group</strong>来保存它,然后在替换字符串中指定<strong>group number</strong>。在</p>
<pre><code>>>> myString = 'I like him, but is he good? Maybe he is good , smart, and strong.'
>>> re.sub(r'(\w)([,?!])' , r'\1 \2' ,myString)
'I like him , but is he good ? Maybe he is good , smart , and strong.'
</code></pre>