"Mastering" 15,000 words doesn't mean that you will be fluent in a language. What if you master all of them and you still can't communicate? Is it worth the risk of putting in so much time and effort? If you understand what you are reading on italki, you probably already have at least 2,000 words. You might even have about 4,000 or even 5,000. With 8,000 words you can read and understand most everything in a newspaper. I wouldn't worry about the numbers, though. If you want to increase your vocabulary by 10 words or 10,000, you will do pretty much the same things. Most importantly, you should try to communicate in English as much as you can, in writing and speaking. When you see that you can't think of a word or an expression to communicate your idea, you should write that down and plan on learning it. Learn everything about the word, not just its meaning. Learn how to use it. Then --and this is the hard part -- you need to find opportunities to write and speak so that you can reinforce the words and make really them a part of your vocabulary. It's not just about the number of words. It's about using the words.

I've got a great benefit from you"BRSwartz" Thank you for this question"Charlene.shentu "

My advice is instead of memorizing words, you learn phrases. In that way you will learn a lot of words and you would know how to use them correctly. You need to constantly practice and use these words in daily conversations in order to master it otherwise you will forget it after a while...no pain no gain:)

Use 'Fifteen Thousand Useful Phrases' (by Grenville Kleiser). Good Luck!

I read that Malcolm X copies the dictionary in his mind when he was imprisoned