Chew and Bite

Chew

To chew is to grind up with the teeth, to masticate. If you chew on something in a literal sense, you are breaking it down with your teeth. To chew on something figuratively is to think it over, to consider it intensely.
Ex: The preschool teachers were always careful to remind their students to chew their food well to avoid choking.
Ex: The students inquired if the teacher might provide a broad essay topic so they would be able to chew on the subject in their preparation for the final exam.
The expression chew the fat means to talk or converse for an extended time. It is usually associated with topics of conversation that are amusing or light. If you are chewing the fat with someone, you are talking about things casually, in a friendly way.
Ex: If you and Jim plan to chew the fat when we go by the Smith's house, let me know and I will bring something to keep me busy during your long conversation.
Ex: Sheila and I did not talk about anything serious when we got together for coffee on Wednesday. It was mostly just a chance to chew the fat.

Bite

As we know, to bite something is to seize or grip with the teeth. The word bite is usually associated with chewing. Bite can also refer to an amount of something you eat, as in have a bite of this pie .
Ex: When you bite into my Uncle John's lasagne, you will know he is a really good chef who spent a lot of time in Italy.
Ex: I don't really want to order a whole dessert, but I would like something sweet. Can I have just a bite of yours?
An overbite or underbite means that one's top teeth close too far over or too far under the bottom teeth for good dental health and for aesthetics. This will usually be corrected by orthodontics or other treatment.
Ex: When my daughter was diagnosed with a severe underbite, her dentist presented us with a plan for how she would correct the problem over the next year.
Ex: Dentists in our organisation want parents to know that an overbite is very common in children, but is usually self-correcting.