The full poem is as follows:
I was discussing this with a friend who speaks Chinese, and they translated this line:
as "Birds and flowers cry and laugh". Their father translated it as something like "Birds laugh and cry", saying that 鶯花 refers to just a bird, a kind of hummingbird based on what he said. My friend noted that 又, in modern Chinese, makes it likely that the action(s) is/are being ascribed either collectively to two things (birds and flowers) or to one thing (hummingbirds).
However, Chloe Garcia Roberts, in her book of translations of Li Shangyin, translates the line as:
The orioles quaver / The flowers laugh
Without getting into the lexical choices here, on what basis does she ascribe 啼 to the bird and 笑 to the flowers? Is this a type of construction specific to poetic voice, to the Tang era, or something else? Or is it just a poetic interpretive choice on the basis of conceptual parallelism: (noun1 noun2 verb1 verb2)=(noun1 verb1)(noun2 verb2). Li Shangyin lived from 813–858, so I assume there has been a lot of time for things to change or have specific uses.
Any insight helps even if it isn't a full answer. Thanks!