Can I use this to improve my english vocabulary? Sometimes I read articles but I don't know what the words mean. It would be nice if you could implement this, if not already.
Only if your native language is not English. There's been a uservoice suggestion to allow it to work in monolingual mode for ages (https://readlang.uservoice.com/forums/192149-general/suggest...) - I've been avoiding this so far since it's a big change to how the inline translations and flashcards would have to work.