Grammar question

Can't comment authoritatively on that...but the second "know" in your second sentence should be "no."

Gotta be careful with that if you want to improve your grammar.

No. It is the same nightmare. That is, the nightmare he was having is also the one he is was living.

Thank you, Frank and Roger. I know that I have a lot to learn, and I appreciate the help.

"But" is a conjunction.

Spelling has nothing to do with grammar, Frank.

Jacob wished he could wake up from this nightmare, which was the one he was living, but this was no delusion.

Forgive me JTT but for some reason I like it better without

There's no need to apologize for your preferences, Dale.

My offering,

Jacob wished he could wake up from this nightmare, which was the one he was living, but this was no delusion.

was not an endorsement for my stylistic preference. Those are pretty much useless to ESLs. They need to, and want to, understand the underlying structure.

I know that that was the way English was taught when you and I were young 'uns but it was only done that way because the vast vast vast majority of English teachers didn't know their verbs from a pennywhistle.

I liked the original better too. "which was" was unnecessary and made the sentence clunky.