Or...The Idiosyncrasies of the English Language as Demonstrated by a 4 year-old American Girl.
I've occasionally heard my 4 year-old, Audrey, say things like "Melinda didn't HAIV" or "The boys weren't being HAIV" (pronounced like waive or wave, pave, shave, crave, etc.). I've never put a lot of thought into it, only assuming that she'd shortened the word "behave".
Today I realized that I was actually witnessing an excellent form of language and grammar assimilation. This is how young children build their vocabulary--they hear a word said and observe it's application, thereby learning it's meaning. Likewise with grammar, they apply common and logical conjugations to their new found vocabulary.
Audrey often heard me issue the instructions "Be nice!" and "Behave!" which, as soon as the lightbulb went on, I realized she heard as "Be nice!" and "Be HAIV!". Being the amazing language learner that she is, she fit what she heard into the patterns she already knew. HAIV must be similar to NICE, since it's used in the same context...therefore it must be conjugated the same as well.
What an enjoyable lightbulb moment!