Hi, Anton Shepelev - Alexander Koryagin!
I read your message from 22.05.2020 14:23

 AS> Hey! The phrase "I forgot he was vegetarian!" (with!?! was' and no
 AS> article before!?! vegetarian') is a quote from the book! Do insist
 AS> on correcting the language of Ramsey Campbell???

Well, taking in mind that it was a horror story, it could mean:
1. He stopped be a vegetarian after that meal.
3. He was a vegetarian and died from that meal.

As for the absence of "a" before "vegetarian" I don't know. IMHO
Englishmen can live without articles if they want. We see it when we
read news titles, for instance. ;)

Bye, Anton!
Alexander Koryagin
english_tutor 2020

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