1. no more than 表示“仅仅”、“只有”(= only),强调少;而 not more than 表示“不多于”、“至多”(= at most)。如:
He is no more than an ordinary English teacher. 他只不过是个普通的英文老师。
He has no more than three children. 他只有 3 个孩子。
He has not more than three children. 他最多 3 个孩子(有或许还不到 3 个之意)。
2. 用于比较两件事物时,no more ... than 表示对两者都否定,意为“同……一样不”(=neither ... nor);而 not more ... than 指两者虽都具有某种特征,但程度不同,意为“不如”、“不及”(= not so ... as)。如:
He is no more a writer than a painter. 他不是画家,也不是作家(= He is neither a painter nor awriter)。
A whale is no more a fish than a horse is. 马不是鱼,鲸也不是鱼(=Neither a horse nor a whale isa fish)。
She is not more clever than he is. 她不如他聪明(= She is not so clever as he is)。