The poet said that personal life is fleeting, but human existence is long-lasting, so "endless" life and "only similar every year" bright moon can coexist. This is a comfort that the poet feels from the beautiful scenery of nature. Although the poet is temporarily sad about life, it is not decadence and despair, but because of his pursuit and love for life. The keynote of the whole poem is "mourning without hurting", which enables us to hear the echo of the voice of the early Tang Dynasty.
Learn something in the future ~ ha