If it was thought carefully,it will have been done better.为什么要用was thought和has been done?

问题描述:

If it was thought carefully,it will have been done better.为什么要用was thought和has been done?
不是问为什么要用被动语态 是为什么用was和has been

这句话的翻译是 如果它被仔细的考虑过的话 它将会被做的更好
was thought是因为它是被动语态 后一句是虚拟语气 表示与将来事实可能相反