"Gordon focused on a seeming oddity first noticed by the linguist Paul Kiparsky; compounds can be formed out of irregular plurals but not out of regular plurals. For example, a house infested with mice can be described as mice-infested, but it sounds awkward to describe a house infested with rats as rats-infested. We say that it is rat-infested, even thought by definition one rat does not make an infestation. Similarly, there has been much talk about men-bashing but no talk about guys-bashing, and there are teethmarks, but no clawsmarks. Once there was a song about a purple-people-eater, but it would be ungrammatical to sing about a purple-babies-eater. Since the licit irregular plurals and the illicit regular plurals have similar meanings, it must be grammar of irregularity that makes the difference.

...

Gordon found that three- to five-year-old children obey this restriction fastidiously. Showing the children a puppet, he first asked them, "Here is a monster who likes to eat mud. What do you call him?" He then gave them the answer, a mud-eater, to get them started. Children like to play along, and the more gruesome the meal, the more eagerly they fill in the blank, often to the dismay of their onlooking parents. The crucial parts came next. A "monster who likes to eat mice," the children said, was a mice-eater. But a "monster who likes to eat rats" was never called a rats-eater, only a rat-eater. (Even the children who made the error mouses in their spontaneous speech never called the puppet a mouses-eater.) The children, in other words, respected the subtle restrictions on combing plurals and compounds inherent in the word structure rules. This suggests that the rules take the same form in the unconscious mind of the child as they do in the unconscious mind of the adult.

...

The children produced mice-eater but never rats-eater, even though they had no evidence from adult speech that this is how languages work.Gordon's mice-eater experiment shows that in morphology children automatically distinguish between roots stored in the mental dictionary and inflected words created by a rule." - The Language Instinct by Steven Pinker

Parents and teachers historically tend to operate under the belief that babies and children do very little thinking of their own. Or that kids' minds are blank slates when they are born and when they start school. It's a common belief that children learn their mother tongue by repeating what the mommy and daddy say. Teachers assume that their first graders take their teacher's word for facts about science.

Yet, none of the above assumptions is true.

There is increasing evidence to the contrary. One-year-olds might be born with a certain grammatical structure or they might be developing it instead of merely imitating mommy's words. First graders already have ideas on why we can see an object and how darkness affects our vision. No matter how 'clearly' a teacher might explain a scientific fact, it often doesn't override the misconceptions the child has already built in his head.

It seems to me that we underestimate children. We never even think to ask them if they have an idea on why the sky is blue or what makes a seed grow into a tree. We assume they don't know until we teach them.

And you know what happens when you assume, don't you?

Previously? Intents.