The man said, "The dengue fever outbreak in Dhaka last year was very concerning." (Change the narrative style of the sentence)

He said to me, "You have done your work." = He told me that I had done my work.

Abir says, "I can help you." = Abir says that he can help me.

Arif said to me, "Do you want my help? = Arif asked me if I wanted his help.

Mother said to me, "Do not run in the sun." = Mother forbade me to run in the sun.
Or, Mother told me not to run in the sun.
Or, Mother advised me not to run in the sun.

They said to me, “Let us decide the matter ourselves.” = They proposed me that we should decide the matter ourselves.

I said to the man, "Do you know anybody here?" = I asked the man whether he knew anybody there.