Have you heard the one about "was" being a word you should cut out of your writing? No, really, it's genuine; I've seen it bandied about among aspiring writers, and even some teachers. Where did it come from? What is it about the past tense form of the most basic verb of all - to be - which makes semi-illiterate ignoramuses put it in the Index Prohibitorum? Seeing a student miserably pulling some perfectly decent sentences around to get rid of was made me so cross that I came over here to work out when you might use was, and why you might not.
- As a main verb: was is the simple past, singular of the verb to be: "Are you happy?" she asked. I was. I said so.
- As a main verb with a complement: I was a fireman [noun]. The box was hers [pronoun]. A school was the obvious answer [noun phrase]. Hamlet was lonely [adjective]. Medea was implacably murderous [adjective phrase].
- As an auxiliary verb in a verb phrase in continuous past tense, in active voice: I was walking. He was rejoicing in the baby. She was playing with the guitar.
- As an auxiliary verb in a verb phrase in simple past tense, in passive voice: He was assaulted. She was bored by the movie. I was distracted from his lecture.
- As an auxiliary verb in a verb phrase in continuous past tense, in passive voice: She was being assaulted by the baby. He was being decorated in the Town Hall. I was being interviewed.
And as far as I can see, after a whizz through Seeley's Oxford Everyday Grammar, that's it. And as far as I can see, it would be very difficult to do without was. These, I'd suggest, are some of the real reasons for those weaknesses:
Plodding sentence structure. If you invariably start your sentences with the (grammatical) subject - which is understandable because that's probably how it occurred to you - then they will have the same structure. Unless you're plodding along in simple past (I walked. I looked around, then I sat.) then there will be a lot of wases: She was walking along the road and she was happy, because the day was hers, the storm was over, and it was gloriously sunny. The cure isn't to routinely cut the wases, it's to learn to read like a writer, and work harder at what you're really wanting to say, and how you should therefore say it.
Telling/informing. If you're informing us that He was irate or I was hypoglycaemic (was+ complement), then you're not showing/evoking how the rage stung in his hands or she felt queasy for want of food. The usual judgements about when to inform/tell and when to evoke/show apply.
Verbs are not adjectives. But in a phrase using was plus -ed forms, such as I was bored at home or she was tickled to think of him, they often act like them. So the usual suggestion (as in that link to my showing/telling post) to be stingy with adjectives holds, as an aspect of the informing/evoking question: are they earning their keep?
Lack of impact. This is about continuous verb forms. If you think in terms of characters being our representatives in the story, She was hitting me doesn't have the same impact - metaphorically speaking - as She hit me. Nor does He was loving me, compared to He loved me. Which doesn't mean you shouldn't use was plus -ing verbs, of course, whatever daft teachers say. Just use it where it's the right tool for the job: She threw me to the floor, then she was hitting me and hitting me and I was curled up, trying to reach for her throat. And I killed her.
Lack of energy. This is about passive voice verbs. Here the grammatical subject of the sentence is not the active person in it, and if the subject is our representative in the experience of the story-world, then our experience of that world isn't active either. So it may well be that I was locked in the ice house is weaker than She locked me in the ice house. Or it may not be: it may be just right, if you were frog-marched into the ice house from behind and have no idea by whom, or why.
Nonsense. As the immortal Turkey City Lexicon nearly puts it: He was putting his key in the door when he leapt up the stairs and got his revolver out of the bureau. But even this isn't really about was: it's about the writer not thinking hard enough about the sequence and relationships of the different actions.
So, yes, was does have a role in various kinds of weak writing, though not in plenty of other kinds. But it isn't the cause of the weakness, so having a "rule" about it seems to me pretty stupid. If you want to think of was as an alarm signal for such weaknesses - a small tool with limited application - then I'm not going to stop you. But it seems to me that you can't possibly work out what to do about a sentence which has set the alarm off, if you don't understand what's really going on inside it. It's a bit like realising that the canary in your mine has stopped singing, without knowing why it's dead or what you should then do. Swapping it for a blackbird isn't going to help.