You could imagine a language exactly like English except it doesn't have connectives like 'and' that allow you to make longer expressions. An infant learning truncated English would have no idea about this: They would just pick it up as they would standard English.

As you deal with more and more complex systems, it becomes harder and harder to find deep and interesting properties.

Language is one component of the human cognitive capacity which happens to be fairly amenable to enquiry. So we know a good deal about that.

Noam Chomsky Quotes