Based on the system of elimination, I would choose - the first is a fantasy but the second is reality (could really happen).
In the first sentence, the poet wishes that the trees are bent due to a boy playing there and swinging on the branches. But the second sentence shows a possible reality, where the cold weather is the one that destroys the birches.
Answer:
I don't notice any grammatical errors.
Explanation:
I think its what it means to be alone