simplified	traditional	pinyin	meaning
你	你	ni3	you (informal, as opposed to courteous 您[nin2])
好	好	hao3	good
您	您	nin2	you (courteous, as opposed to informal 你[ni3])
你好	你好	ni3 hao3	hello; hi
您好	您好	nin2 hao3	hello (polite)
对不起	對不起	dui4 bu5 qi3	I'm sorry; excuse me; I beg your pardon
没关系	沒關係	mei2 guan1 xi5	it doesn't matter