Quora is one of the best social networks in terms of questions and answers. Needless to say, there are numerous questions and answers about the English language. This is a particularly good example: 

QUESTION

I am a non-native English learner. How much vocabulary can I learn in a day?

ANSWER

You don’t acquire words.
You learn them when you process these words through your brain in a meaningful context. If there is no context, these words won’t be in your brain for longer than a few hours. In more practical terms, if you are trying to acquire a word by reading it in the book, it is unlikely that you will remember it after you read it.
But if you make a memory association, or better, a short funny story that repeats this word many times, you won’t even need to make any effort memorizing it.
The most important thing in learning a language is not acquiring new vocabulary. It is using the language irrespective of the number of words in your vocabulary. Being able to use a few simple phrases is worth 10,000 flashcards with words you never use.