each human being 后面接单数还是复数?

问题描述:

each human being 后面接单数还是复数?
it would be a blessing if each human being were stricken blind and deaf for a few days
我觉得后面应该接WAS 而不是WERE

这里用WERE是虚拟语气,表示假设.和主句would一致.
表示事实的话是用单数.