Direct to Indirect (Imperative Sentence)
An imperative sentence has a command, order, request or suggestion.
To convert an imperative sentence to indirect speech the verb (said/told) of reporting verb is replaced by some specific verbs like requested, ordered, advised, suggested, etc.
For example,
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Rayna said to me, “Please help me to complete my homework.” (Direct speech)
Rayna requested me to help her with her homework. (Indirect speech)
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Doctor said to him, “Drink plenty of water”. (Direct speech)
Doctor advised him to drink plenty of water. (Indirect speech)