When the green leaves are not decreasing, what season is described by the four or five sounds of orioles?

There was a period in the middle of Sanqu Road (Song Dynasty).

Plum blossoms are yellow, the sun is shining, the streams are exhausted and the mountains are gone.

The shade did not reduce the road, but increased the sound of four or five orioles.

In May, the rainy season in Jiangnan is sunny. The author swam to the end of the stream by boat. When he returned, he just took the mountain road. He saw that the shade was not thicker than before, and the sound of orioles from the depths of the shade added a lot of fun. This shows that the poet loves nature.