Teachers often discover CI after several years, even many many years, of using other methods. Old habits are hard to break. A question that often comes up s how to transition from former methods to one that stresses Comprehensible Input. Where to find help?
The short answer is: We don’t. How do you know that “He goed” is not grammatically correct? At some point in their infancy, most children will say “He goed”. Then they stop saying it, long before a school teacher tells them that it is not good grammar. Good grammar, like vocabulary, is acquired before it