“IT WAS not in a literal way, but in my head it was a battle.”

I would be more inclined to say that it is just a problem with the participle.

Beef, too!

But read as a pair of sentences, it is complete:

I love eating chicken. Beef, too!

The words “I love eating” are implied in the sentence “Beef, too!” But I’m afraid I don’t see the implied words in your sentence that carry it to completeness. First of all, both sentences are a bit confusing in that fighting a fish is often a literal battle of life and death (for the fish, at least). So, the reader has to wonder what was going on with this particular fish and you that you had hooked it, but had to imagine the ensuing battle? And even if it wasn’t a battle, per se, it was at least a struggle, right? Why imagine a battle when you’re in a struggle? Fishing isn’t a sport of imagined battles, but one of real conquests over nature and animal life.

So, maybe all of your readers are already confused by the time we get to that controversial second sentence. At best, it is clumsily written! Consider something more like: “Not literally, but in my head.” Or “Not literally, but in my imagination.” Etc. The more I read it, the more I tend to agree with you that it probably IS a complete sentence. But trust me when I say that you may have confused your instructor so much that he or she HAD to ding it for something! Would you have been happier if he said that it was an awkward sentence? Or had he had “problems” with the two sentences together?

Your only objective is to write clean, uncluttered, well-managed sentences. I would strongly recommend that you read the book, On Writing Well. It will change your writing life!

1. The sentence can’t be understood on its own. If you just read that sentence without the one before it, no one would have any idea what you are talking about.

2. A sentence fragment is a sentence separated from the main clause. The first sentence you wrote is the main clause, and it is indeed separated!

To fix it, take out the period and put in a comma or semicolon.

“I had hooked a large fish and I was beginning to fight it; not in a literal way, but in my head. It was a battle.”

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