They never knew what __(happen)to the world in a hundred years
问题描述:
They never knew what __(happen)to the world in a hundred years
答
would happen
答
would happen
主句谓语是knew从句用过去将来时
答
would happen 主句是过去时 从句应用过去时,但有in a hundred years
所以用过去将来时