根据短文理解, 完成下了各题。
Do you still get free plastic bags from the supermarkets? Things have changed.
China has banned（禁止）free plastic bags at shops and supermarkets, and people have to pay for using plastic bags. The rule started on June 1, 2008. It came because our country tried to make litter less. Making super-thin（超薄）plastic bags has also been banned.
The Chinese once used about 3,000,000,000 plastic shopping bags a day, and they have caused pollution of the environment (环境污染). The bags have become a main cause of plastic pollution because they are easy to break and people throw them away here and there. So the Chinese people are encouraged to bring their own bags for shopping.
What kind of shopping bag is the best to bring? Some students in Chongqing have a good idea. They make their own shopping bags. They use old clothes to make cloth bags（布袋）, and send them to their parent s as presents. They also ask their parents and friends to use cloth bags instead of plastic ones. They think it is their duty to protect（保护）the environment.
