請回答第 19 題至第 22 題：
        Modern cities can be great places in which to live. They can also be hellholes, overcrowded, dirty, noisy, andpolluted. Much of the blame for that   19   traffic congestion. But city planners are fighting back and   20   withinnovative ways to make some of the world’s great cities good to live in once again. Let’s take London for example.Elected in May 2000, mayor Ken Livingstone vowed to tackle congestion by charging vehicles coming into the citycenter. In February 2003, his administration introduced a daily $12 toll for entering a 22-square-kilometer central zone. Ina 2003 poll, 63 percent of Londoners said they supported the charge, for the simple reason   21   it works. Fiftythousand fewer vehicles a day go into the city. Roads are less congested, there are fewer accidents, and journey hours arefaster. London’s success has not gone   22   . “Every major city in the world has asked us about congestion charging,”says Transport for London spokesman Graham Goodwin.
【題組】19
(A) lives on
(B) lies with
(C) consists of
(D) rings up