Scientists have discovered the world’s largest known field of sea grass. They did it using videos shot by some sea animals. The work should help protect the sea grass, and also shows off a creative way to explore the ocean.

Sea grasses are flowering plants that normally grow in shallow waters near coasts. They grow in thick fields, known as meadows. Sea grass meadows help clean the ocean water, and provide food and home for many sea creatures. Importantly, sea grass meadows also help in the fight against the climate problems. That’s because they store a great deal of carbon — the harmful pollution that’s making global warming worse. Damaging (破坏) these sea grass meadows can release this pollution again, so it’s important to protect them.

However, the ocean is too huge for humans to study all by diving (潜水). A team of scientists decided to have tiger sharks help with the research because tiger sharks live underwater, swim fast and spend a lot of time in sea grass meadows.

The researchers attached cameras and other trackers to seven tiger sharks. After catching the sharks, the scientists worked quickly to attach the equipment, then let them go again. The cameras were designed to fall off after a few hours and float (漂浮) to the surface. Tracking signals helped the scientists find the floating cameras and collect the videos the sharks had taken over the sea floor. Putting all the data together, the scientists learned that the waters around the Bahamas are home to the largest sea grass meadow ever discovered.

The project is important for several reasons. Since sea grass is so valuable in fighting global warming, it’s important to know where it is. Oliver Shipley, a leading scientist, says, “If we don’t know where it is, we can’t protect it.” The program also shows how useful large sea animals can be in helping to learn more about life under the sea. Shipley says animals like tiger sharks “… are going to take us to new places that we didn’t know.”

【小题1】What helped the scientists discover the largest ever field of sea grass?

A．Ships working underwater.	B．Videos taken by tiger sharks.
C．Images shot from passing planes.	D．Exploration of professional divers.

【小题2】What does the underlined word “release” in paragraph 2 mean?

A．Let out.

B．Cut down.

C．Clear away.

D．Wind up.

【小题3】What does paragraph 4 mainly talk about?

A．The ways of following large sea animals.

B．The steps of fixing cameras to the tiger sharks.

C．The unique functions of the signal-tracking equipment.

D．The process of finding the world’s largest known sea grass meadow.

【小题4】What can we learn from the last paragraph?

A．Sea grass is of high value in research and business.

B．Humans have benefited from pollution-free oceans.

C．Scientists have solved the climate problems effectively.

D．Ocean animals can help uncover more secrets of nature.