Multiple variables in rewrite mod

I am new in rewrite mod and i want to make something like when user go to: http: mysite.qqq/news/it/some_news1 real URL will be: http:// mysite.qqq/index.php?s=news&d=it&i=some_news1. But i don't know how to make this. I need help.

Now i have .htaccess:

RewriteEngine On
RewriteRule ^([a-z_]*)/?$ index.php?s=$1 [QSA]

And i am thinking to add something like:

RewriteRule ^([a-z_]*)/([a-z_]*)/([a-z0-9_]*)/?$ index.php?s=$1&d=$2&i=$3 [QSA]

But it doesn't working开发者_C百科.

RewriteRule ^/(.+?)/(.+?)/(.+?) mysite.qqq/index.php?s=$1&d=$2&i=$3 [QSA]