B
Wetlands play an important role in the ecosystem. However, about 35 percent of the wetlands have been lost in the past 50 years. Hoping to protect the wetlands, Cui Luoyao and Lyu Haoyan, two schoolgirls from Beijing created a mudskipper(弹涂鱼) amphibious robot(两栖机器人). They won the gold award of the 19th Soong Chingling Award for Children’s Invention.
“We wanted to make a simpler robot to help collect data(数据), but traditional robots faced problems in wetlands,” Cui said. As an amphibious fish, mudskippers are small and can move freely in wetlands. Inspired(启发) by 
the littl
e creature, they added a special chest and tail fin(鳍) to their robot. The fin could help the robot move freely on land and swim underwater. They also learned coding to control the robot with their phones from far away, up to 300 metres. What was more, they put in different sensors(传感器) to see plants and check water quality(质量).
But things didn’t always go well. How to keep the main electronics(电子器件) dry when the robot went underwater was a big problem during testing. “The 3D printed parts we used couldn’t seal(密封) well,” Lyu said. After trying different ways, they found that placing rubber rings in the gaps(缝隙) worked well to stop water from getting in.
After successfully controlling their robotic mudskipper on land and underwater, they were happy with their success. “I feel so proud because our robot can help look into the places that people cannot reach,” said Cui.
(
A
)4. The two girls created the robot to ______.
A. protect wetlands B. check water quality
C. complete their schoolwork D. learn more about amphibious fish
(
A
)5. What does “the little creature” in Paragraph 2 refer to?
A. The mudskipper. B. The wetlands. C. The robotic fish. D. The wild animals.
(
B
)6. What did the two girls use to control their robot?
A. A tail fin. B. Their phones. C. A computer. D. Different sensors.
(
D
)7. How did the two girls keep the electronics dry when the robot was underwater?
A. By sealing the robot with tape. B. By adding a special cover to it.
C. By using more 3D printed parts. D. By putting rubber rings in the gaps.