Mod rewrite 为什么重写模块不能在.htaccess中工作

我正在尝试让我的htaccess文件使用以下内容：

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

这很简单：

RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^index/([^/]+)/?$ index.php?action=$1 [QSA,L]

当有人单击

example.com/index/something

，它将发送到

index.php？action=something

好吗

RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^index/([^/]+)/?$ index.php?action=$1 [QSA,L]