How to Learn Vocabulary Effectively

It doesn’t matter what language you’re trying to learn. You just can’t avoid having to memorize a whole bunch of words and phrases, but this doesn’t have to be a grind.

Humans speak according to Zipf’s law. Which means that the second most word is used ½ times as much as the most used word. And the third most used word 1/3 times as much. We make clever use of this phenomenon.
The Pareto-principle or the 80/20 rule states that 80% of the output comes from 20% of the input. If you, instead of learning words randomly, start learning with the most used words first, you will understand more of what is spoken faster.
In general, the top 10 words in any language account for 25% of all words used, top 100 words for 50%, top 1000 words for 70% and the top 2000 for 80%.
This is not the same for every language, but roughly it is. That means, that if you would learn the 2000 most used words of the language you want to learn, you would be able to understand 80% of all words used. If you learn 50 words a day, which is not that impossible trust me, you would be at a very decent level after 2000/50= 40 days!

The Routledge Frequency Dictionaries have made this even easier for you. Instead of putting the words in alphabetical order. They are sorted by frequency. They do not have every language out there, but they have the most popular. They’re quite pricey as well. However, I would say this is the best tool you can buy for learning your language, they save you so much time.

I’ve put links to all the Routledge dictionaries I could find down below:
Spanish
German
Portuguese
Mandarin
French
Czech
Arabic
Japanese
Russian
Dutch
Korean
Turkish
Persian