How to Turn Your Existing WordPress Installation into a Subfolder Multisite
This article explains how to make a WordPress multisite with subfolders and how to turn an existing WordPress installation into a subfolder multisite.
"subdomains"
Best Way to Make Your WordPress Site Multi-Lingual
Don't use a plug-in to make your WordPress site multi-lingual. Use sub-folders or sub-domains. I explain why in this article.