How Many Words Do You Need to Know to Speak Fluently?

What does it mean to "speak" a language fluently? 

Well, the meaning of the word "fluently" depends on your definition of "fluency". I've talked about my own definition of fluency in depth elsewhere, but here it is again: 

"The linguistic ability, combined with cultural awareness, to smoothly and confidently interact with native speakers in a meaningful way". 

You might notice that this definition of fluency refers only to speaking a language with people; the truth is, though, that fluency comes in several forms according to how a language is used. Just as you can be a fluent speaker, you can also be a fluent reader, a fluent writer, and a fluent listener. Fluency in one of these areas, however, does not guarantee fluency in others. 

It's completely possible for a person to be a capable and competent reader of their target language, for example, without having any genuine ability to speak it. The "fluencies" you have as a language learner ultimately depend on the depth of the skills you have cultivated. 

A person who cultivates "overall fluency", then, is a person who can comfortably read, write, understand, and speak a language. He or she can read books and magazines, speak with natives and non-natives in a wide variety of situations, compose natural-sounding texts, and watch movies, debates, and TV series without difficulty. 

That's what fluency looks like to me. When people talk to me about fluency, though, they often ask about words. 

"Doesn't the number of words you know also affect how fluent you are?", they ask. "How many words do you need to know to be able to speak fluently?" 

It's a good question, and a relevant one. 

Of course, you can't be fluent if you don't know enough words to read, write, speak, or listen in a fluent way. 

But what exactly does it mean to "know" a word? 

It's hard to say. Maybe even impossible to say. Words themselves are hard to define. We tend to think of them as a collection of spoken sounds (or written letters) that forms a specific meaning. 

But the truth is that meaning is dependent on context. 

For example, If I say the word "game", I could be talking about the board game "Monopoly", or a deer being hunted in the forest. I could even be talking about something completely different! You'd never know without referring to the words surrounding the word "game" exactly which definition I meant. 

Confusingly, words can be simultaneously full of meaning and absolutely meaningless, depending on where and how they are used. 

So, unfortunately, I can't easily quantify how many words you need to "know" to be a fluent speaker of your target language. 

Beyond these general guidelines, here are the five ways I approach learning words anytime I learn a language (with minor adjustments for specific languages). 

1. I don't count words.

It's an obvious truth that the more words I know, the more fluently I will be able to speak. Beyond that, though, it's useless to worry about the exact numbers. If I focus solely on steadily learning more and more words over a long period of time, then I can rest easy knowing that eventually I'll have more than enough words to achieve fluency.

2. I get massive input.

I can't learn words if I don't encounter them in my learning activities. Following that logic, the best way to encounter as many words as possible is to expose myself to as much of the language as possible, through massive input. As I gain exposure, my brain will naturally and steadily pick up words, and absorb their meanings through context. I gain this exposure through reading multiple pages of a book every day (affiliate), regularly listening to podcasts, and watching YouTube videos.

3. I build goals based on habits.

Instead of worrying about the exact number of words I need to know to be fluent, I create a system of habits that will help me maximize my opportunities to learn new words. For example, I have often set goals of reading two, five, or even ten pages a day of an interesting book in my target language. If I can do that, then I know my mental vocabulary of words will inevitably grow.

4. I focus on learning the words that are most useful to me.

Earlier, I mentioned that some words are used more frequently than others, and that makes them more useful. But the utility of a word can also depend on who you are and what you do as a person. For example, I am heavily interested in astronomy, so words like "spaceship", "astronaut", "orbit", and "gravity" are much more useful to me than they would be to the average language learner. When I meet with a language tutor, I always choose topics like this that interest me, so I get lots of opportunities to use these words, and so I remember them better. I also learn phrases and sentence fragments related to these topics, which helps me learn "chunks" of words at a time, rather than just one by one.

5. I seek out a wide variety of life experiences through my target language

Have you ever noticed how children are completely fluent in their mother tongues, even though they only know and understand a limited number of words? This is due to something I call "linguistic competence". Even though they have limited vocabularies, children develop lots of real-life experience experimenting with those vocabularies in real-life situations. They know how to ask for what they want, get attention, and describe the world around them, because those are language skills they need to survive and thrive. I like to develop my own "linguistic competence" by testing out my language skills in a wide range of situations that are most relevant to my life. If I didn't do this, and instead learned my languages only through reading books, I'd have an extremely hard time doing things like buying a train ticket (true story), ordering food at McDonalds, or even just having a conversation with a native.

So, that's it! At the end of the day, words do play a huge part in how well you speak your target language, but how you learn words is far more important than the actual number of words you know. If you apply the strategies I've described here, then you'll soon develop powerful systems for learning all the words you need to be a competent, fluent speaker of your target language.