Hi everybody

Is this sentence grammatically correct:

" The number written in the catalog is 30"

If it's correct, would you please tell me what is structre of it ?

Best regards
It's correct. The number [that/which is] written in the catalog is 30. I'm not sure which structure you have in mind. Perhaps written? I call it a relative clause equivalent but I think many native speakers refer to it as a reduced clause. Catalog is more American than British (catalogue).

Thank you so much Emotion: stick out tongue