It was Wang Wei who sent Yuan Er to Anxi.
Weicheng Song / Sending the Second Envoy of the Yuan Dynasty to Anxi
Author: Wang Wei
The morning rain in Weicheng is light and dusty, and the guesthouses are green and willow-colored.
I advise you to drink another glass of wine. There will be no old friends when you leave Yangguan in the west.
Translation
The light rain in the early morning moistened the dust on the ground in Weicheng. The air was fresh and the hotel was greener. I sincerely advise my friend to drink another glass of wine. It will be difficult to meet old relatives when you leave Yangguan to the west.