Question

How did frog plan to destroy bird's spirit?

Answer 1

The frog deviced the plan to finish the nightingale. The Frog compelled The Nightingale to sing non stop in the name of training. He forced her to sing even though it was not in good and favourable weather for her to sing and her throat was not clear. He gave her no rest in that unfavourable weather.
So due to exhaustion the nightingale burst her vein and died..

Answer 2

The frog wanted to be the undisputed king of Bingle bog. He sang to his delight and couldn't stand any kind of rivalry.even though he was hated by all but there was no one to complete with. He is extremely passionate about his loud and unmussical voice and has an exaggerated opinion about himself.