In my experience (English natively, Chinese, Japanese & Spanish conversationally, and an interest in the subject with knowledge of about a diversity of other languages), English and Chinese can tolerate a lot of "error" and still maintain strong communication. You can mix up the order of words, you can use the "wrong" vowel for a given word, and there are a lot of different words that mean similar things, but are close enough. All of these aspects make the language understandable, even when the language skills of the speaker or listener are poor. Many different dialects of Chinese use tones very differently, have slightly different word meanings, and have different word orders - and communication in the language persists fairly well even when one speaker has a very different syntax, emphasis, and even vocabulary.
This idea is not really true for languages like Japanese, where mixing up a vowel can render the entire sentence confusing to a listener. And word order is fairly strict (if still expressively diverse). You can't just smash together some ideas and expect someone to really understand you. Similar is true for other more strict romantic languages (Latin is like that as well).
And so both English and Chinese seem to make be amenable to trying out and playing with not just new vocabulary, but new syntax, grammars, and phenomes.