Indirect speech, also called reported speech or indirect discourse, is a means of expressing the content of statements, questions or other utterances, without quoting them explicitly as is done in direct speech. For example, He said "I'm coming" is direct speech, whereas He said he was coming is indirect speech. Indirect speech should not be confused with indirect speech acts.
In terms of grammar, indirect speech often makes use of certain syntactic structures such as content clauses ("that" clauses, such as (that) he was coming), and sometimes infinitive phrases. References to questions in indirect speech frequently take the form of interrogative content clauses, also called indirect questions (such as whether he was coming).
In indirect speech certain grammatical categories are changed relative to the words of the original sentence. For example, person may change as a result of a change of speaker or listener (as I changes to he in the example above). In some languages, including English, the tense of verbs is often changed – this is often called sequence of tenses. Some languages have a change of mood: Latin switches from indicative to the infinitive (for statements) or the subjunctive (for questions).
When written, indirect speech is not normally enclosed in quotation marks or any similar typographical devices for indicating that a direct quotation is being made. However such devices are sometimes used to indicate that the indirect speech is a faithful quotation of someone's words (with additional devices such as square brackets and ellipses to indicate deviations or omissions from those words), as in He informed us that "after dinner [he] would like to make an announcement".
Changes in form 
In indirect speech, words generally have referents appropriate to the context in which the act of reporting takes place, rather than that in which the speech act being reported took place (or is conceived as taking place). The two acts often differ in reference point (origo) – the point in time and place and the person speaking – and also in the person being addressed and the linguistic context. Thus when a sentence involves words or forms whose referents depend on these circumstances, they are liable to change when the sentence is put into indirect speech. In particular this commonly affects:
- personal pronouns, such as I, you, he, we, and the corresponding verb forms (in pro-drop languages the meaning of the pronoun may be conveyed solely by verb inflection).
- demonstratives, such as this and that.
- phrases of relative time or place such as now, yesterday and here.
There may also be a change of tense or other modifications to the form of the verb, such as change of mood. These changes depend on the grammar of the language in question – some examples can be found in the following sections.
It should be noted that indirect speech need not refer to a speech act that has actually taken place; it may concern future or hypothetical discourse; for example, If you ask him why he's wearing that hat, he'll tell you to mind your own business. Also, even when referring to a known completed speech act, the reporter may deviate freely from the words that were actually used, provided the meaning is retained. This contrasts with direct speech, where there is an expectation that the original words will be reproduced exactly.
- It is raining hard.
- She says that it is raining hard. (no change)
- She said that it was raining hard. (change of tense when the main verb is past tense)
- I have painted the ceiling blue.
- He said that he had painted the ceiling blue. (change of person and tense)
- I will come to your party tomorrow.
- I said that I would come to his party the next day/the following day. (change of tense, person and time expression)
- How do people manage to live in this city?
- I asked him how people managed to live in that city. (change of tense and question syntax, and of demonstrative)
- Please leave the room.
- I asked them to leave the room. (use of infinitive phrase)
The tense changes illustrated above (also called backshifting), which occur because the main verb ("said", "asked") is in the past tense, are not obligatory when the situation described is still valid:
- Ed is a bore.
- She said that Ed was/is a bore. (optional change of tense)
- I am coming over to watch television.
- Benjamin said that he is/was coming over to watch television. (change of person, optional change of tense)
In these sentences the original tense can be used provided that it remains equally valid at the time of the reporting of the statement (Ed is still considered a bore; Benjamin is still expected to come over).
In Latin grammar, indirect speech is called ōratiō oblīqua. An indirect statement or question can serve in the place of the direct object of a verb related to thought or communication.
An indirect statement is expressed by changing the case of the subject noun phrase from nominative to accusative and by replacing the main verb with an infinitive (without changing its voice or tense).
- Amo libertatem. ("I love freedom")
- Dicit se amare libertatem. ("He says that he loves freedom")
- Rex dedit omnibus leges. ("The king gave laws to everyone")
- Credo regem dedisse omnibus leges. ("I believe that the king gave laws to everyone")
- Videbimus permulta cras. ("We shall see very many things tomorrow")
- Speras nos videturos esse permulta cras. ("You hope that we shall see very many things tomorrow")
- Tertium non datur. ("No third possibility is given")
- Docuit philosophus tertium non dari. ("The philosopher taught that no third possibility is given")
- In Senatu imperator interfectus est. ("The emperor was killed in the Senate")
- Audivi imperatorem in Senatu interfectum esse. ("I heard that the emperor was killed in the Senate")
In the case of predication via a copula (typically esse), the case of the predicate adjective or noun changes from nominative to accusative.
- Sum felix. ("I am happy")
- Dicit se esse felicem. ("He said that he was happy")
An indirect question is expressed by changing the mood of the main verb from indicative to subjunctive. It is normally appropriate to retain the word that introduces the question.
- Я не люблю шоколад. ("I don't like chocolate")
- Она сказала, что не любит шоколад. ("She said that she didn't like chocolate", literally "She said that (she) doesn't like chocolate")
Free indirect speech 
Free indirect speech is a form of indirect speech where the reported utterance is expressed independently, not in a grammatically subordinate form. An example is given below.
- Quoted or direct speech:
- He laid down his bundle and thought of his misfortune. "And just what pleasure have I found, since I came into this world?" he asked.
- Reported or normal indirect speech:
- He laid down his bundle and thought of his misfortune. He asked himself what pleasure he had found since he came into the world.
- He laid down his bundle and thought of his misfortune. And just what pleasure had he found, since he came into this world?
- Loos, Eugene E.; Susan Anderson; Dwight H. Day, Jr.; Paul C. Jordan; J. Douglas Wingate. "What is indirect speech?". Glossary of linguistic terms. SIL International. Retrieved 2010-06-20.
- Allen, Joseph Henry; Greenough, James Bradstreet; D'Ooge, Benjamin Leonard. New Latin Grammar for schools and colleges. Ginn, 1916.
- page 584, paragraph 580: declaratory sentences in indirect discourse;
- p. 380, par. 586: questions in indirect discourse.
- Bache, Carl. 2000. Essentials of Mastering English: A Concise Grammar. The Hague: Mouton de Gruyter, p. 139.
- Downing, Angela & Philip Lock. 2002. A University Course in English Grammar. London: Routledge, p. 301.
- McArthur, Tom. 2005. Concise Oxford Companion to the English Language. Oxford: Oxford University Press.