If you grew up around the time that I did and watched Saturday morning cartoons, the title to this post instantly brings a School House Rock tune to mind. I liked them so well that I set up a tape recorder next to the TV on Saturday mornings, hoping to record School House Rock songs to listen to later. (This was before CDs and DVDs.)
Combined with the occasional comma, I've noticed that there is quite a bit of usage confusion going on out there when it comes to conjunctions. If you suffer from conjunction disfunction, here are a few tips to help you.
Conjunctions can join words, phrases, or clauses.
Bob and Fred are tormenting the neighbor's cat. (Compound subjects)
The neighbor's cat is hissing and clawing. (Compound verbs)
The cat is jumping into the air and onto Bob. (Compound phrases)
Bob is bleeding, and Fred is laughing. (Compound sentences)
The main takeaway here is that the two parts which you join with a conjunction have to be equal to each other. This means you cannot join a word and a phrase with a conjunction. They are not equal.
Bob and ran to the store.
Obviously joining a subject and a verb with a conjunction doesn't work. It doesn't even sound right, so it's unlikely anyone will make this mistake. However, there are other possibilities which are more subtle.
Bob, frustrated (word) and showing quick thinking, (phrase), is dropping the angry cat on Fred's head.
This sounds a little better, but it's still wrong. You can't put a word and a phrase together with a conjunction. In the School Rock vein, it's like trying to hook up a bicycle and a train car. Not pretty.
So today's lesson is two-fold. Don't try to join unequal sentence parts with conjunctions, and don't mess with your neighbor's cat. It will be bad. Very bad.