A．can keep people away from TV violence

　　B．are welcomed by families with small children

　　C．are concerned about the proper use of language

　　D．are unsuitable for the whole family to watch together

　　解析：选D　细节理解题。根据文章第一段第二句"... making it hard for concerned families to find channels suitable for young eyes."可知，数字电视服务提供的大多数频道不太适合全家人一起观看。故选D项。

　　22．Which of the following can best describe Discovery Channel?

　　A．Relaxing.　　　　　　　　 B．Touching.

　　C．Commercial. D．Professional.

　　解析：选A　推理判断题。根据文章第二段的"Discovery tries to do in an entertaining manner - educating the masses about everything"可知，探索频道寓教于乐，由此可推知，该频道应是令人放松的。故选A项。

　　23．If people want to know about what a traditional family is like, they can choose ________.

　　A．Fox Family B．Nickelodeon

　　C．ABC Family D．Living

　　解析：选C　细节理解题。根据文章第五段的最后一句"The need for this channel was felt after ABC observed the lack of proper family type U．S. channels."可知，该频道是在缺乏合适的美国家庭类频道的情况下设立的，因此，如果人们想要了解传统家庭是什么样子的就可以选择ABC Family频道。故选C项。

　　B

　　(2018·安徽省"江淮十校"联考)Krubera Cave in the western Caucasus Mountains is the deepest known cave in the world. An international team prepared to descend into Krubera. The team members hoped to be the first cavers to reach a depth of 2,000 meters, brought five tons of equipment and other necessities with them, and established camps at key locations along the route. They worked for up to 20 hours each day.

In the third week, progress was blocked at 1,775 meters by a sump - a cave passage filled with water that gives cavers few options. There are basically three techniques available: dive through it, empty it, or go around it. Gennadiy Samokhin dove to the bottom but was disappointed. "No chance to get through，" he said. Searching for a way around the sump, Garcia Dils risked entering a waterfall of near freezing water and discovered that his dry