Question

"your song must be your own" what is ironic here?

Answer 1

"your song must be your own" it was said by the frog but he himself was forcing the bird to sing in a voice like him. And he forced her to sing in a better voice.

Answer 2

first the frog told nightingale to take training from frog nd keep daily lessons from him but when the nightingale died he said stupid bird ones song must be his or her's own the turning back of frog is ironical here
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