> How can China expect the rest of the world to use Chinese when even they themselves don't know it 100%?

And there goes Shakespeare. On average there's 15,000 words per play. I bet most readers do not have the education to know every single word in that 15,000.

"The Second Edition of the 20-volume Oxford English Dictionary contains full entries for 171,476 words in current use, and 47,156 obsolete words. To this may be added around 9,500 derivative words included as subentries." [1]

[1]: https://en.oxforddictionaries.com/explore/how-many-words-are...