When we quote word for word what somebody says, we use inverted commas (quotation marks) and we repeat exactly the original utteranceSomething that somebody says in a specific context.. This is called direct speech:

David: Have you seen The Two Towers? (original utterance)
David asked, "Have you seen The Two Towers?" (direct speech)

However, if we give the same meaning without repeating the exact words, we do not use inverted commas and certain changes may be necessary. This is called indirect speech (or reported speech because we report what has been said):

David (to Tom): Have you seen The Two Towers? (original utterance)
David asked Tom if he had seen The Two Towers. (reported speech)

Sometimes, however, there is no real original utterance, only an implied one:

I don’t know where she lives. (implied utterance: Where does she live?)
I had no idea where my keys were. (implied utterance: Where are my keys?)
I knew that the lock had been changed. (implied utterance: The lock has been changed.)

• Punctuation in direct and reported speech

Guiding questions: indirect speech
Indirect speech Punctuation in direct and reported speech