Fledglings became independent when self-foraging was energetically more profitable than begging food from the parents, whilst parents significantly reduced the meal mass delivered to the fledgling when the fitness increment from new nesting exceeded that from attending their current young.

Post-fledging food supply from the parents was relatively greater than during the pre-fledging period, averaging 176 g per day, but declined significantly at the end of the post-fledging period.

He uses a lot of words about the cloud,sun and flying birds in his poems which are full of his real emotion.

Through the full use of the image of the flying birds, we can see a figure of feudal scholar with an energetic nature; a vivid, refined - tasted person who respects and therefore merges into nature; a person rich in interest and full of steady, sure and distinct personality and a well-developed figure with optimistic, unrestrained and unconventionally graceful quality.