BBC – “Learning a new language can be tricky, but how many words do you need to know before you can actually get by in a foreign tongue? That was the question posed to BBC Radio 4’s More or Less programme by one frustrated listener. Despite learning German for three years, and practising nearly every day, they still couldn’t seem to retain more than 500 words I was hoping,” they wrote, “you could give me a shortcut, by working out how many words we actually use on a regular basis.” To work out how many words you need to know to be able to speak a second language we decided to look into how many words we know in our first language, in our case English. We considered dusting off the dictionary and going from A1 to Zyzzyva, however, there are an estimated 171,146 words currently in use in the English language, according to the Oxford English Dictionary, not to mention 47,156 obsolete words. To quote a well-known internet meme “ain’t nobody got time for that”. What we needed was a mathematical cheat. Fortunately for us somebody beat us to it. Linguists Paul Nation and John Read (who doesn’t love a bit of nominative determinism?), along with their colleague Robin Goulden, came up with a test involving only 50 words. Their theory is that if you count up how many of the 50 words you understand and multiply the total by 500 you are able to estimate your total English vocabulary. Words start off simply enough; dog, editor, immense but they quickly become more obscure, for example would you know how to use “oleaginous” …in a sentence? And now Paul’s free English vocabulary size test, using 100 words, is available online...If you learn only 800 of the most frequently-used lemmas in English, you’ll be able to understand 75% of the language as it is spoken in normal life…”