bag、packet与case有何区别?

bag、packet与case有何区别? bag和packet有何联系和区别? On this case 与in this case 有何区别呢 packet bag 两个都用做包名词时,有没有什么区别 packet bag 两个都用做包名词时,有没有什么区别 a bag with food和a bag full of food及a bag of food 有何区别?with与of for fear that 与 in case有何区别?3Q in case 与in case that有什么区别? in case 与in case that of有什么区别 box与case的有什么区别? in case与if有什么区别? bag 与backpack有什么区别? in case of 与 in case 有什么区别 中文分别是什么 packet 和pocket 有什么区别和用法不同阿、 pencil box 与pencil case有什么区别? box与case的有什么区别?如题` 先谢叻~ in case of与for fear of有什么区别? is this your bag?与is this bag yours?有什么区别