Bobby had someone to play with him, someone to love him and care for him, while out there on the hillside Kathleen was alone--all alone.

VOA: special.2010.05.15

So, think about the birches as a tool, another tool, but this time a tool for play, a tool for playing alone.

把桦树看成一种工具，另一种工具，但是这次是玩的工具，只是玩的工具。

耶鲁公开课 - 现代诗歌课程节选