18．Cars make our lives more convenient．But they can also be a problem．For example，fossil fuel（化石燃料） cars mainly cause air pollution．
To improve the environment，many countries are developing electric vehicles（EVs，電動車）．Among them，China is taking a leading role and has created the world's largest EV market．
Last year，over 40 percent of the 753，000 EVs sold in the world were sold in China，more than twice as many as the number sold in the United States．
"Filling up a fossil fuel car with gas（汽油） is more expensive than charging（充電） an electric car，" said Wu Hao，who bought an electric car this year．
However，there are still some problems．It can be hard to find charging piles（充電樁） and the cars can't go far before needing to be recharged．
Some of these problems are being solved．In 2014，China had 31，000 charging piles．Now China has the world's largest EV charging network，with more than 167，000 charging piles in total．
Developing EVs is one of many efforts that China has made to cut down pressure on its environment after the government promised to stop increases in carbon dioxide emissions（二氧化碳排放量） by 2030．
"As China goes，so will the world's car industry，" The Wall Street Journal said．China has taken a leading role in the world's electric vehicle industry．
（1）
mainly cause air pollution according to the passage．
A．Subways
B．Sharing bikes
C．Electric vehicles
D．Fossil fuel cars
（2）Over
electric vehicles were sold in China last year．
A．150，600
B．167，000
C．301，200
D．753，000
（3）What did Wu Hao think of charging an electric car？
A．It's more expensive than filling up a fossil fuel car with gas．
B．It's less expensive than filling up a fossil fuel car with gas．
C．It's as expensive as filling up a fossil fuel car with gas．
D．It's as cheap as filling up a fossil fuel car with gas．
（4）Which country has the world's largest EV charging network now？
A．America．
B．Germany．
C．China．
D．England．
（5）What is the passage mainly about？
A．China has taken a leading role in the world's electric vehicle industry．
B．Electric cars will disappear in the future．
C．There is no problem using electric cars．
D．How to deal with air pollution．
