English regularly violates its own rules and additionally has no correcting body (Swedish has central body that dictates language rules for example).

That's part of why it's so difficult to fully master, and there are rules (sentence structure) for clarity, but there's no actually solid rules for pronunciation (it differs depending on word) or even what words are really proper words (there are central dictionaries that largely agree, but there are also "Hinglish", patois and the other creole dialects).

English steals aggressively from other languages, since that's its history. Other languages might borrow some words but there's multiple branches of these inside english. You can use English with only latin-root words, or English with only Germanic-root words and both are as valid english as each other.

Easy to learn; awful to master.