Chinese names originated the Eastern ordering of names, where the family name precedes the given name. A man called Wei and belonging to the Zhang family is called “Zhang Wei” and not “Wei Zhang”. So you can call him his name or Mr. Zhang.
中文姓名沿袭了东方的姓名排序，姓在名的前面。一个男生叫“伟”，且属于“张”姓家族，那么被叫做“张伟”而不是“伟张”。你可以直接叫他的名字或者张先生。
“xiānsheng” is used to address a man and “xiǎojiě” always to a young woman who’s unmarried.
“先生”是对男性的称呼，而“小姐”一般称呼未婚的年轻女性。
