The English language would surely be incomplete without it, and all communication would come to a stop, but would it really be so bad to hide it in the closet once in a while? Most writers would be sorry-out-a-luck, and would die a slow, painful death, but hey, wouldn't the sacrifice be worth it? =P
Here's the thing. The more I learn, the more I notice the difference between fabulous writing and terrible writing. You want to know the difference between the two? For this post, it's the word was.
Almost always, a sentence would be better without it. Is it laziness on our part that we leave that boring word in there? Granted, it's needed at times, but for the most part, it's not. The point is still the same. It's worth the time to go through your manuscript and see if that word can be replaced by something better.
1. Beth was smart. or The answers saturated Beth's mind, and her fingers flew across the test paper as she wrote the correct numbers.
2. It was so hot. or I fanned myself as I watched a mirage ripple over the heated pavement.
3. He was the cutest boy at school. or I stared, unable to deny the heated attraction I felt when his gaze flickered over me.
These examples were off the top of my head. I'm sure they could be improved, but you get the idea. Fix all the was words (for past tense) and is words for present and you'll be surprised at how great your book becomes!
And watch out for that first sentence summary. Don't say, "Beth was smart" and then go on to explain why by putting both sentences (in my example) together. It takes the power out of your paragraph, the umph out of your story, and the mystery out of your words. You DON'T want that, no matter what. Are there exceptions to that rule? Only if you're Stephen King maybe.