有"人到了，问候也到了"之意，其余几个选项都没有这双重的意义。故A项正确。

　　15．选C　只有早春的花儿才显漂亮和珍贵。故C项正确。

　　16．选B　女儿的来访，给了作者很多启示，她也想到了自己的母亲。因而拿起电话打给自己的母亲。

　　17．选A　作者的母亲接听了电话。下一段第一句中的 answered 是线索提示。故A项正确。

　　18．选D　根据第一段中的 smallest 可知应选 big, 和后面的 little 相对应。故D项正确。

　　19．选C　19空所在句与上一句构成转折关系。故C项正确。

　　20．选B　女儿的来访让作者很高兴，作者打电话给母亲，就在作者挂掉电话之前，母亲说 "你让我一天都非常开心"。 make one's day "使某人非常高兴"。 hang back "犹豫，畏缩"； hang up "挂断电话"； hang out "晾晒(衣服)"； hang on/upon "紧紧抓住"。

Ⅳ.阅读理解

　　Do you know the open­air art gallery in London's Blackall Street？Probably not.Not many Londoners know it either，but Henri does and he is willing to show it to you.

　　Henri used to sleep in parks until he met a charity (慈善机构) that helps homeless people get back on their feet by becoming tour guides.

　　Rather than show traditional London sights，"Unseen Tours" take people off the beaten track.Henri has been teaching tourists about the history and architecture of Shoreditch，where he slept on public benches for three years.

　　When he felt separated from the society，contact with the volunteer network "The Sock Mob" gave Henri hope."Not everyone just looked down on me，" he said.The tours aren't the only actions trying to help those who have suffered a misfortune to stand tall again.

　　An innovative (创新的) college for homeless people in London，the first of its kind in the country，is attracting hundreds of students.The Recovery College，set up by St Mungo's charity，is providing courses designed to improve technical skills and life skills.

　　According to Andy Williams，who helps to organize the college，the most popular courses have proved to be about raising self­confidence and developing self­pride.

Steve，now in his 50s，told a reporter how much of a difference it makes to "have a bit of confidence"．He had difficulty learning to read and had to leave school when he was 12.Because Steve's problem was not recognized at the time，he was "seen to be unable to read or write"，and suffered with depression and alcohol addiction.He says the status of "student" is itself important for people who are used to being treated as outcasts (被遗弃者)．