in good years,the patchwork of green fields that surround the Stown bustles with farm workers,many of them in the area just for the season. A. surround the S town bustles with farm workers,many of them B. surrounds the S town bustles with farm workers,many of whom 答案是A,为什么不是B? patchwork 到底是单数还是复数? 用many of whom 可以吗?