有细微的区别
1.in addition
used for adding an extra piece of information to what has already been said or written 用于句首,表示对已经提及过的信息的添加【要用逗号和后边的句子隔开】
如：People gain valuable work experience and,in addition,employers can afford to employ them.
2.besides
1）in addition to someone or something else that is being mentioned 用于提及过的【不用逗号和后边的句子隔开】
如：
Besides making money,the company aims to set high standards of quality anddesign.
2）used when you are adding another stronger reason to support what you are saying但是多一个用法,就是可以添加一个更有说服力的理由在支持自己说的事情【这个时候要用逗号隔开】
It's too late to invite any more people.Besides,you know how Tim hates parties.
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