因此不能做段首;A段落these tools开头,出现代词,不能组为段首;B段落many discussions are not so successful,出现词汇so,为代词,指代上面说的successful discussion,因此不能做句首;这样只剩D和E段落,D段落开头Carnegie would be right if…,这里出现了对人物观点进行...