Question

English as a Second Language English Vocabulary, Grammar and Idioms
1

(a) What I was concerned were those comments
(b) What I was concerned was those comments.

As far as I know, by and large, the two sentences are correct, but (b) is more formally correct.

Question: Which one is more idiomatic/natural to native speakers?..

Thanks

2

What I was concerned about was those comments.[YSaerTTEW443543]

TOEIC listening, photographs: A girl with boxes[YSaerTTEW443543]

3

Beeesneees,
“What I was concerned was those comments.”
Do you say this sentence is wrong?
But I admit “What I was concerned about was those comments.” is correct.
Please comment.

4

Yes that sentence is wrong without ‘about’.