What do you mean by drawing lots for exams?

This is composed of two words, not an idiom. Cowherd refers to cowherd and weaver girl. ChanJuan is beautiful, beautiful or refers to the beauty. The meaning of the whole sentence should be to praise the beauty of other people's husband and wife, which is often used to praise others when they get married.

Chan Juan's interpretation is to depict a beautiful gesture; Ancient poems are often used to describe women, as well as the moon, flowers and so on. From "Selected Works of Zhang Heng": "The business of chewing turns around and increases the number of Juanjuan." . "