never fail to do 与must比较谁更委婉
问题描述：
never fail to do 与must比较谁更委婉
有个句子：
you never fail to study hard
语气和must比较谁更委婉
答
never fail to do
never fail to do 与must比较谁更委婉
有个句子：
you never fail to study hard
语气和must比较谁更委婉
never fail to do