CISSYZHANG74
你好！你所给的问题有多种表达形式：①时间状语从句When you pick something up, you must hand it in.orWhenever you pick something up, you must hand it in.②宾语从句You must in what you pick up。orYou must hand in whatever you pick up.③定语从句You must hand in something/everything/all that you pick up.祝你开心如意！
薇枫1988
must +动词原形是一定要,必须的意思,强调主观条件或这是命令的口气.have to是不得不强调客观条件使你不得不做,甚至可以认为是你不想做的意思,却要做的意思.例如:The homework have to be handed out tomorrow.明天不得不交作业了.(可能作业有一定的期限,明天是最后一天你不得不去交了.)The homework must be handed out tomorrow.明天一定要把做业交上去.(自己下的决心,今天一定要把它做好,明天交了.)You must hand out your homework tomorrow.你明天必须交做业(老师命令你的)
