Indirect statements are generally introduced by the verbs to say, to tell, to announce, and in official style by the verb to inform.

With the verbs to tell and to inform the person addressed is always mentioned. With the verbs to say and to announce the person addressed may or may not be mentioned. If it is mentioned, the preposition to is used.

Direct Speech Indirect Speech
She said (to us), “There are interesting magazines in the reading-hall.” She said (she told us) that there were interesting magazines in the reading- hall.
She said (to us), “I am leaving for good.” She announced to us that she was leaving for good.
The monitor said to us, “There will be a meeting to-night.” The monitor informed us that there would be a meeting that night.

One night the telephone bell rang and he (Cowperwood) informed her that he was compelled to remain at the office late. (Dreiser)

The verb to say is used to introduce both direct and indirect speech if the person addressed is not mentioned. If the person is mentioned, the verb to tell is preferable; if the verb to say is used, the preposition to is necessary.

Direct Speech Indirect Speech
She said, “I’ll be back directly.” She said she would be back directly.

You said that you would give me back my letter, didn’t you? (Wilde)
The Miller said to his wife that he would go down and see Little Hans. (Wilde)

The verb to tell is used to introduce indirect speech only; the person addressed must be mentioned.

Direct Speech Indirect Speech
She said to us, “I’ve received an interesting letter.” She told us she had received an interesting letter.

An emphatic statement tinged with emotion is often introduced by the verb to declare.

Direct Speech Indirect Speech
She said, “It’s the dullest book I’ve ever read.” She declared it was the dullest book she had ever read.

The innkeeper declared that he really wanted to go to Oakbourne. (Eliot)

Other verbs are also used to introduce statements. According to the character of the statement, the verbs to promise, to remark, to remind, to assure, to admit, to deny, etc. are frequently used.

Direct Speech Indirect Speech
He said to me, “ I hope you have not forgotten that there will be a meeting tonight.” He reminded me that there would be a meeting that night.
He said, “The text is rather difficult.” He remarked that the text was rather difficult.
He said, I did speak to her about that.” He admitted having spoken to her about that.
He said, I never spoke to her.” He denied having spoken to her.
The child said to his mother, “I’ll never disobey you again.” The child promised his mother never to disobey her again.
She said to them, “I’ll certainly come in time.” She assured them that she would come in time.

I spoke to the station-master and also to the innkeeper of the village. Both of them assured me that he (my friend) had gone for a voyage round the world. (Conan Doyle)