10 . 阅读下面短文,在空白处填入1个适当的单词或括号内单词的正确形式。
Several studies in recent years have suggested that ride-sharing services like Uber can 1 (worse) traffic problems in cities, 2 continue to have high rates of private vehicle ownership.
The new study, 3 (conduct) by the not-for-profit group Union of Concerned Scientists, represents 4 attempt to center on how ride-sharing services affect pollution. The research examined the effects of ride-sharing services 5 the environment of seven American cities.
Overall, the researchers reported that ride-sharing trips now result in an estimate 69% more climate pollution on average than the 6 (replace) trips. The study explains that the same passengers could have chosen to travel by bus, train, bike or on foot.
One of the big reasons they give for this result is that usually ride-sharing vehicles 7 (drive) with no passengers in the car. This happens 8 drivers are either waiting for rider requests, are on the way to pick up passengers, 9 are driving in between pickups.
The study urges services like Uber 10 (work) to increase the number of pooled rides and electric vehicles on the road, and to improve connections to public transportation centers.