wordpress - Why does the URL include /blog/ on one of my Multisite WP sites and not the other? -

can 1 tell me why have 1 multisite includes /blog/ in url , other 1 doesn't?

eg:

http://site1.com/blog/article

http://site2.com/article

how can change on site site basis?

and when change how should redirect current urls new location.

what code .htaccess file?

thanks! :)

if used subdirectory install of wpmu .htaccess must below

rewriteengine on rewritebase / rewriterule ^index\.php$ - [l]  # add trailing slash /wp-admin rewriterule ^([_0-9a-za-z-]+/)?wp-admin$ $1wp-admin/ [r=301,l]  rewritecond %{request_filename} -f [or] rewritecond %{request_filename} -d rewriterule ^ - [l] rewriterule ^([_0-9a-za-z-]+/)?(wp-(content|admin|includes).*) $2 [l] rewriterule ^([_0-9a-za-z-]+/)?(.*\.php)$ $2 [l] rewriterule . index.php [l]