题目内容：

He has no sisters or brothers.这里用or He has no sisters and no brothers.这里用and

优质解答

He has no sisters or brothers中的or是连词“也不”意思,前面用no 否定sisters,后面用or否定了brothers;
He has no sisters and no brothers.,前面用no 否定sisters,后面用and起连接作用,再用一个no才可以否定掉brothers,因为and是没有否定意义的.