system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why have languages like Spanish not changed that much over the past several hundred years, but English has?

In my Spanish class recently, we read a story written in the 1200's, and it was perfectly comprehensible. I only had to look up a couple of the words. The grammar was a little bit archaic, but it wasn't difficult to understand at all. Compare this with, for example, the Canterbury Tales in English; these were written in the 1300's, and it is literally a completely different language from modern English. Even being a native English speaker, having looked at the Canterbury Tales in their original prose, I can only pick out the occasional word here and there. Even Shakespeare, which is considerably more modern, is, at least for me, harder to understand than very old Spanish texts. What has made English change so much, whereas Spanish has been so consistent?
gpt
English experienced some major changes around that time that Spanish did not. In 1066 the Normans, who spoke French, took control of England. The fact that the ruling class spoke French greatly affected the native English language and a lot of French words made their way into the language.

Additionally, there was something called The Great Vowel Shift in English that happened from around 1350 - 1600, in which speakers changed the way they said vowels. The end of this period is also when spelling was becoming standardized, so you end up with some weird spellings trying to reflect changing pronunciations. Spanish didn't have a great vowel shift, probably due in part to the fact that it has fewer vowel sounds.

This combination of a changing vocabulary and pronunciation/spelling makes it hard for modern English speakers to read things written before the end of the vowel shift, but we can read most of the stuff that was written towards the end of that time such as Shakespeare's plays and poems.