Task：Some cities have vehicle-free days, when private cars, trucks, motorcycles are banned in the city center. Public transportations like buses, taxis and metros are advised. To what extent do you think the advantages outweigh the disadvantages.
Sample answer：
In some cities around the world, people are not allowed to use private vehicles on some particular days and only public transports are available. From my point of view, this practice brings more benefits than drawbacks.
This approach does lead to some inconvenience for citizens especially for working people. Compared with taking bus or subway, it is more convenient and comfortable to drive ones own car. With more people taking buses or metros on vehicle-free days, it will add to the burdens of the already overloaded public transport system. The bus terminal may be jam-packed with commuters, which will make people more discontent.
Nevertheless, we cannot deny the contribution it brings to pollution reduction and energy saving. As we know, air pollution has become a severe problem, since it is causing irreversible damage to the environment in many countries and the exhaust fume emitted by various kinds of vehicles is one of the culprits of air pollution. In this sense, if there were few vehicles on the road, it will relieve this problem at some extent. In terms of energy saving, fuels are in such short supply that we have to do everything we can to save energy. Apart from this, another benefit lies in the fact that it will remind people to take public transportation instead of using private vehicles. Definitely more attention could be paid to the advantages brought by using public transports with the implementation of this measure.
All in all, it is a wise practice since all the inconvenience and discontent is temporary as long as governments invest more money on the development of public transport infrastructure. And what is more important is that less pollution will be produced and more energy will be saved, which will benefit the human beings in a long term.