I think
The old man sitting there is like a stone.is right.
This is a sentence of 「 〜ing」
If the first sentence,there are two verbs (was,looked)
I see. I'm sorry,I couldn't find a mistake on the second sentence...
Certainly,the first sentence is 過去進行形(was 〜ing)
But the second sentence is not 過去
So you are right! I also think both of them are wrong.
If 過去進行形(過去形)
「The old man sitting there was like a stone.」
So it is okay!
Thanks~
But the second sentence is 現在進行形 , I think 過去進行形 or 現在完了 is right .
And you are right, there are tow Verbs...
So... I think both of the two sentences are wrong.