It has been snowy for two days为什么不用snowing

It has been snowy for two days为什么不用snowing It has been snowing ____several days.A .since B.for C.in D.b he has been ill for 3 days 为什么不用sick It's been snowing for 3 days and it's quite cold these days The fish(has been dead)for two hours and a half.为什么不用has die It had been（一直）snowing very hard for days．Jigs and Reads had It was snowing very hard for days.Nicholas's two dogs,Sa for been she here two has days 怎么连啊 请问：He has been deed for two days.是什么时态? The hero has been dead for two years.为什么用dead ?而不用died ? 为什么It is two months since she left Beijing用is不用has been She has been ill for over two days .(改为同义句） she has been ill