任务型阅读。
People often complain( 抱怨) about buses in Shanghai. The dirty smoke from the buses pollute our city. Buses are always full of            ① and it’s ② to get a seat. ⑵有时人们得等很长时间，but the bus doesn’t come. And some bus drivers stop the bus suddenly, so people on the bus may fall down and get hurt easily. It is natural that not so many people like to take the bus. ⑶If the bus service can be made better, there will be fewer traffic problems. Then people will feel it convenient to go anywhere in our city.
在空格处填上合适的词。
①     ____    ②      ____  
将⑵处译为英文。                                 .
将⑶处译为中文。
                                                。
在文章中找出下句的同义句, 并写在横线上。
People on the bus may fall down and get hurt easily because some bus drivers stop the bus suddenly.
                                                          
找出文章的中心句。
                                                      。