"I'll clean the car tomorrow, "Hasnain said to his father.

Hasnain told his father that he would clean the car tomorrow

Hasnain promised to his father he will clean the car tomorrow

Hasnain said to his father the he will clean the car the following day

Hasnain told his father that he would clean the car the following day

Remove inverted commas.

Change the pronoun

Tomorrow into the following day

Direct: "I'll clean the car tomorrow, "Hasnain said to his father

Indirect: Hasnain told his father that he would clean the car the following day

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