Talk about the main contents of The Book of Songs with examples.

The Book of Songs is the first collection of poems in China, mainly before the mid-Spring and Autumn Period. The Book of Songs mainly divides the wind, which refers to the national wind. They are poems with local color in some vassal countries and regions, most of which are folk songs, and some of them are works of the aristocratic class. Guofeng collected the works of Nan Zhou, Zhao Nan, Feng Wei, Feng Wang, Qifeng and other 15 vassal countries and regions. Elegance is a poem by Wang Ji of the Western Zhou Dynasty, which is divided into elegance and indecency. Ode is a kind of music song used to worship ancestral temple, including Zhou Song, truffle and Shang Ode.