Transform the given sentence into Direct Speech.
He promised that he’d behave himself.

Correct option is D

The given sentence is in indirect speech: "He promised that he’d behave himself." To convert it into direct speech, one must reconstruct what the person likely said at the time of making the promise. In direct speech, he would have used the first person ("I") and directly declared his intention ("I'll behave myself"). The contraction "I’ll" (I will) is the natural and idiomatic form for a self-promise, matching the modal intent and immediacy of a spoken promise. Also, the reflexive pronoun changes from "himself" (reporting) to "myself" (speaker’s direct words).

Information Booster

About the Transformation Rule:

Work/Author: The transformation from indirect to direct speech, especially promises, is a rule found in most major English grammar resources, including Raymond Murphy’s English Grammar in Use and Huddleston & Pullum’s A Student’s Introduction to English Grammar.

Genre: English Grammar, Syntax, Speech Reporting.

Summary of the Direct Speech Construction:

Indirect speech version ("He promised that he’d behave himself") removes the speaker’s original words and third-persons the subject.

In direct speech, the reporting verb ("He promised") is followed by what he said, using first-person pronoun ("I") and direct intent ("I’ll behave myself").

Contractions (“I’ll”) are common in promises and offers for natural spoken English.

Additional Knowledge

Incorrect Options Explained:

(1) He promised, ‘I must behave myself.’

"Must" expresses strong necessity or obligation, but is less natural for reporting a personal promise about future action than "I'll" (will). "I'll" conveys commitment, which matches the original meaning.

(2) He promised, ‘I would behave himself.’

Incorrect for two reasons: it uses "would" (which, in direct speech, does not show a firm promise as "will" does), and the reflexive pronoun "himself" is incorrect—when speaking directly, he would use "myself".

(3) He promised, ‘I would behave myself.’

"Would" again lacks the sense of firm, personal promise. "Will" or "I'll" is needed for committing oneself to future action in direct speech.