Our mental dictionary, the list of about 50,000 words we keep in our heads, tells us that left and waffle can either be nouns or verbs. Parsing is the way we understand how words in a sentence relate to each other. We can represent the relationships of words in sentences by parsing trees , like the two below. The branches on these trees tells us how each word is related to all the other words in the sentence. The point is that we must apply knowledge about words and sentence structures which is not present in the sounds in order to interpret such sentences as this one either way.
Sentence structure is an invisible but essential part of the mental processing of language.
It is a major component of humor in all languages. So, language tells us much about ourselves, not only how we speak but why we laugh. It makes us laugh. Still, it has been the object of serious research for 4,000 years. The best news is that you can find out much more about it right here at this web portal.