I thought I knew about commas before I started looking into them. It was a learning curve.

Looking into. . .
But, and other little words that join things together, and. . .
Because
But
The rule for but is the same as that for and, or, nor, for, so, and yet. (These are called coordinating conjunctions, but you don’t need to remember that.)
We’re back to essential versus nonessential information here. If the conjunction follows a main clause that makes sense on its own, it’s added information, so add a comma:
David sprinkled more salt, but he still couldn’t eat the spinach.
If both clauses are necessary to make any sense, no comma is needed:
David sprinkled more salt but still couldn’t eat the spinach.
There is another way of looking at and and but that I find easier to remember.
If clauses have a subject on both sides of the conjunction, there should be a comma.
I phoned Emma earlier, but I haven’t heard back from her.
I phoned Emma earlier but haven’t heard back from her.
If the second clause assumes the same subject without naming it... or him or her… (in this case, I ) you don’t add a comma.
Peter got up and made his bed before heading down for breakfast.
Peter got up, and he made his bed before heading down for breakfast.
(A case of adding a comma when you add a subject? Or am I pushing this tip too far?)

Because
What rule applies here?
I didn’t watch the film, because it starred Alfredo Bloggins.
I didn’t watch the film because it starred Alfredo Bloggins.
You might be forgiven for thinking that this is one situation where the discredited ‘pause’ myth might apply. However, there is a grammatical reason.
In the first sentence – with the comma – because refers to the whole of the first clause. The point is that I didn’t watch the film; the reason I didn’t watch is added information. The first part of the sentence will make sense without giving a reason why.
The whole purpose of the second sentence is to explain why I didn’t watch the film. This because is essential to the meaning of the sentence – it’s the whole point of it. Since this information isn’t added, it wants no added comma.
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Another helpful resource. . .
The most exhaustive comma crib in one place must be Purdue OWL; another brilliant resource all-round, at . . .
https://owl.english.purdue.edu/owl/resource/607/2/

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I posted this a day early in case you thought it was a wind-up.
It’s all true. Honest.
Copyright © 2023 cathy-cade.com – All rights reserved.
I do read all of these Cathy, but don’t remember them when writing.
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Me neither. (That’s one reason why I wrote them all down, having looked them all up at some time or another when we were putting our first anthology together.)
And sometimes you want to ignore some of them in the interest of not having too many commas in one sentence.
Anyway, a writer’s first draft should be just as it comes out of our heads. It’s on reading it back that I find that it doesn’t sound how I meant it to. And sometimes my first edits don’t do the job either. Reading the story out loud is best – ideally a day or two after I finish writing it.
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I thought I understood commas and other punctuation but after reading all 4 parts, I feel as if I’ve tied myself in knots LOL x
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You can imagine how I felt when I started editing the anthologies. My mail order proofreading course hadn’t gone into such detail. In fact, now I’ve learned more, I think they rather dodged the topic so as not to put us off.
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Thanks, Cathy, it’s beginning to percolate through I think.
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I’m still digesting some of it myself (hence the reblogs)
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I was following you fine until I came to the last pair. I cannot understand how the first sentence needs a comma despite your explanation. But as a complete geek, I have enjoyed the series immensely.
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It’s that second ‘he’ that makes the difference. although you can ignore all of it if it results in too many commas.
Basically, I’ve decided, if in doubt, leave it out. If it makes sense on a second reading, leave it as it it.
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I abuse commas, I can’t help it, I’m a huge fan of bunching small ideas into one sentence, like bananas. That’s why we need editors! xxoo, C
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Their main purpose is to help the reader make sense of the text. If they’re not needed for that, I’m tending to leave them out… whatever Grammarly or ProWritingAid tells me.
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