However， they are not so welcome in robot market because they are extremely slow and have a hard time operating through the water. But that may change soon thanks to a self-driven soft robot created by researchers at the University of California， San Diego. The recently-developed robot， which resembles a paper lantern， was primarily built using soft materials. Its flexible ribs are attached to a circular plate at both ends. An adjustable nozzle（喷嘴）fitted on one side helps draw in and jet （射出） water each time the robot shrinks. The resulting jets of water enable it to swim forward， similar to a squid （乌贼）. A plate holds a waterproof component that can house a camera to record data， which is of great value to further development of the robot. It also has its own power source， allowing it to float autonomously for long periods of time. "Essentially，we recreated all the key features that squids use for high-speed swimming. This is the first robot that can achieve these jets of water by changing its body shape，which improves swimming efficiency，" said Professor Michael T. Though the squid robot has not been tested in open waters，it successfully swam around coral and fish in a large tank in the UC San Diego Birch Aquarium. What's more， the robot clocked an impressive speed of 18 to 32 centimeters per second， or about half a mile per hour. Though nowhere close to real squids， it is faster than most other soft robots. "After we were able to improve the design of the robot so that it would swim in a tank in the lab，it was especially exciting to see that the robot was able to successfully swim in a large tank among coral and fish， showing its possibility for real-world applications，" said Caleb Christianson，who led the study as part of his Ph. D paper.（1）Why were the previous soft robots seldom used？ ____

Soft robots， which can move around the ocean without harming sea life， are ideal for underwater exploration. However， they are not so welcome in robot market because they are extremely slow and have a hard time operating through the water. But that may change soon thanks to a self-driven soft robot created by researchers at the University of California， San Diego.
    The recently-developed robot， which resembles a paper lantern， was primarily built using soft materials. Its flexible ribs are attached to a circular plate at both ends. An adjustable nozzle（喷嘴）fitted on one side helps draw in and jet （射出） water each time the robot shrinks. The resulting jets of water enable it to swim forward， similar to a squid （乌贼）. A plate holds a waterproof component that can house a camera to record data， which is of great value to further development of the robot. It also has its own power source， allowing it to float autonomously for long periods of time.
    "Essentially，we recreated all the key features that squids use for high-speed swimming. This is the first robot that can achieve these jets of water by changing its body shape，which improves swimming efficiency，" said Professor Michael T. Though the squid robot has not been tested in open waters，it successfully swam around coral and fish in a large tank in the UC San Diego Birch Aquarium. What's more， the robot clocked an impressive speed of 18 to 32 centimeters per second， or about half a mile per hour. Though nowhere close to real squids， it is faster than most other soft robots.
    "After we were able to improve the design of the robot so that it would swim in a tank in the lab，it was especially exciting to see that the robot was able to successfully swim in a large tank among coral and fish， showing its possibility for real-world applications，" said Caleb Christianson，who led the study as part of his Ph. D paper.
（1）Why were the previous soft robots seldom used？ ____
A. Their application places are limited.
B. They do great damage to sea life.
C. They are very difficult to control.
D. Their advertising effect is hot good.
（2）What's the similarity between the newly-developed robot and squids？ ____
A. Their body material.
B. Their general speed.
C. Their power source.
D. Their swimming pattern.
（3）What can we learn about the squid robot according to Paragraph 3？ ____
A. It is the first robot that can transform.
B. It will function well in open waters.
C. It has every feature that a squid has.
D. It can defeat most other soft robots in speed.
（4）What's Caleb Christianson's attitude towards the newly-developed robot？ ____
A. Positive.
B. Critical.
C. Uncaring.
D. Doubtful.