A lot of questions have been dedicated to how evolution of English got many constructs of the old either fall out of use, merge, or evolve into different forms but still with 1:1 relation to original. English of the Victorian times has been significantly more complex than modern day English.
But I'm quite convinced elements of grammar didn't just die or evolve into uniform counterparts — I'm fairly sure entirely new ones would be born over time, or simple cores would branch out into multiple, significantly different, more complex variants.
Can you identify elements of contemporary English grammar, that would simply baffle one taught only in Early Modern English? Common, everyday constructs of grammar that don't have simple direct counterparts of the old, or are significantly more complex? New tenses? Inflection where there was none?