第一，旅客人数不断增加，自2015年起增长了1亿人次，这加大了运输能力和服务保障的难度。

First, the number of passengers keeps growing, increasing by 100 million from 2015, whichincreases the challenges of transport capacity and service guarantees.

youdao

第一，旅客人数不断增加，自2015年起增长了1亿人次，这加大了运输能力和服务保障的难度。

First, the number of passengers keeps growing, increasing by 100 million from 2015, whichincreases the challenges of transport capacity and service guarantees.

youdao