没有图时,that和this的具体区别（That is Tom/This isTom） 选哪个?

没有图时,that和this的具体区别（That is Tom/This isTom） 选哪个? this和that的区别 that 和this的区别? this that these those的区别!（要具体） this 和that用法的区别 this that的区别 that this it的区别 this that it的区别 THIS、THAT和IT的指代用法有什么区别? THIS,THAT和IT的指代用法有什么区别 问this that these those there 的用法和区别~ that is why和 this is why用法的区别 that和where which等的用法区别 具体的、 evening 和night的具体区别是什么呢?比如tonight和this evening 的区别是? this和that有什么区别 the和this that有什么区别 How do you know this 和How do you know that 有没有区别?有的话区别是什么? 元素符号和化学式的区别没有分清,具体点