题目

If we are to succeed, we'llhave to provide something our competitors don't so that we can be c in the business world. 答案：【1】competitive下列四个句子：①这首歌调子太高，我唱不上去 ；②引吭高歌；③她是唱高音的；④请勿高声喧哗．其中“高”字指音调的是 （ ）A．①② B．②④ C．①③ D．③④