题目内容：

    Engineers have put a huge garbage collector to gather plastic material in the Pacific Ocean between California and Hawaii, the world's largest spread of garbage, twice the size of the state of Texas.

The Ocean Cleanup organization created the collector. The group's founder, Boyan Slat, an inventor born in 1994, was just 16 when he was moved to clean up the oceans when he was on a dive and saw more plastic bags than fish

Last Saturday, a ship pulling the pipe-shaped floating barrier left San Francisco. Attached to it is a screening skirt that hangs three meters down in the water. The screen is designed to collect the plastic as it moves through the water. Sea animals can safely swim under the barrier

The cleanup system also comes with lights powered by the sun, cameras, and other special devices, so the system can communicate its position at all times. That way a support ship can find it every few months to remove the plastic that has been collected.

Shipping containers will hold all the plastic gathered , including bottles and fishing equipment and are expected to be back on land within a year. Then the plastic will be recycled. The free-floating barriers are made to survive extreme weather conditions and damage from continual use. They will stay in the water for twenty years , thus collecting 90% ofthe garbage in the area.

The Ocean Cleanup has received $ 35 million in donations to pay for the project, hoping to put 60 free-floating barriers in the Pacific Ocean by 2020. "It's important to turn off the taps on plastic entering the ocean, but I also think people can do more than one thing at a time to deal with this problem," Slat said.

1.What drove Slat to invent the collector?

A. The interest in invention

B. His failure to dive due to rubbish.

C. The sight oftoo many plastic bags

D. His knowledge ofgarbage in the Pacific Ocean

2.How does the floating barrier work?

A. It reaches into the water to collect the plastic

B. It has large containers to produce power

C. 'It forms barriers to protect sea animals

D. A ship drags it along in the ocean.

3.Which does the underlined word "it" in paragraph 4 refer to?

A. The support ship.

B. The floating barrier

C. The plastic to be recycled.

D. The position of special devices.

4.What is important for protecting the ocean according to Slat?

A. Sending more collectors into the ocean

B. Inventing more ocean cleanup devices

C. Stopping plastic from entering the ocean

D. Banning the use ofplastic bags in boats