The boy said ______ couldn’t he work out the problem but his teacher didn’t know how to do it. A. though B. never C. hardly D. not only 答案:D依据倒装语序(couldn’t he work)排除A项;由于使用了couldn’t,就不能再用never或hardly,故选D项。另外not only与后文的but也一致。 命题“两直线平行,内错角相等”的题设是( ),结论是( ).