it is strange that sb should do与have done的区别意义与使用环境

it is strange that sb should do与have done的区别意义与使用环境
it is strange that sb should do与have done的区别
意义与使用环境

it is strange that sb should do与have done的区别意义与使用环境
it is adj.+...+(should)+do 是一种虚拟语气的
而have done 是对已发生过的事情表示很strange

should do（表提出建议）还没有做某事 have done 在过去已完成了某事

就是句型it is strange that sb should do