小题1:B
小题2:C
小题3:A
小题4:D
小题1:细节题：从第一段的But the river traffic is not nearly so interesting as the beautiful scenery along the banks and hillsides. 看出水上之旅没有沿岸的风景有趣，所以选B。
小题2:细节题：从第一段的Wine from the Rhine Valley is famous all over the world.看出这里酒就是全世界著名的。选C。
小题3:细节题：从文章的第二段On our right we can see a rocky cliff over 400 feet high. 看出选A。
小题4:细节题：从第二段的最后一句话：It is a song about a beautiful siren (妖妇) who has lured(引诱) many sailors to their deaths.得知D项正确，是关于一个美丽但危险的妖妇的。