The hall was dark and spooky.
I walked down the hall.
He yelled at me from across the hall.
That office is two doors down the hall, on the left. This hall has many doors.
I will sprint down the hall.
In the sentence given, "round" is a noun.
we accommodate numerous people in the hall
The hotel was happy to accommodate its guests.
I entered the hall with elation as I knew I was about to be married.
How do you get to Carnegie Hall? Intonation, intonation, intonation.
That dining hall is large enough to accommodate 150 guests.
I went to a cinema hall AND enjoyed the movie.
The root word "mon" in "admonished" means to warn or scold someone firmly. In this sentence, the hall monitor cautioned or rebuked you for shouting.
Study hall is two words. An example sentence could be "we will meet in the study hall after lunch".
The nouns in the sentence, people and hall, are both concrete nouns. There are no abstract nouns in the sentence. The use of the word 'protest' is the trick. As a noun, protest is an abstract noun, but in your sentence it is the verb form 'to protest', not a noun.