Apache高手请看看！！！！

请问下面的话是什么意思啊？是怎样匹配的？

RewriteRule ^/gate/big5/(.*)/([^./]*).(gif)$ /gate/big5/$1/big5_$2.$3 [E=OLDURL:http://$1/$2.$3,NC]


RewriteRule ^/gate/big5/(.+) http://$1 [P,L,NE]
RewriteCond %{HTTP_COOKIE} Referer=/gate/big5/([^/]+)/
RewriteCond %{REQUEST_FILENAME} !^/gate/big5/(.+)
RewriteRule ^/(.+) http://%1/$1 [P,L,NE]

RewriteRule ^/gate/gb/(.+) http://$1 [P,L,NE]
RewriteCond %{HTTP_COOKIE} Referer=/gate/gb/([^/]+)/
RewriteCond %{REQUEST_FILENAME} !^/gate/gb/(.+)
RewriteRule ^/(.+) http://%1/$1 [P,L,NE]