题目内容：

The days of having to carry a phone charger everywhere could soon be over. Michigan researchers have revealed a major breakthrough in harvesting energy from human motion. They say it could lead to smartphones powered for a week by the motion of a swipe(重击).

Michigan State University’s low-cost device, known as a nanogenerator, has already been tested. Scientists successfully operated an LCD touch screen, a bank of 20 LED lights and a flexible keyboard, all with a simple touching or pressing motion and without the aid of a battery. The groundbreaking findings, published in the journal Nano Energy, suggest “We’re on the path toward wearable devices powered by human motion,” said Nelson Sepulveda, associate professor of electrical and computer engineering and lead researcher of the project.

“What I foresee, relatively soon, is the capability of not having to charge your cell phone for an entire week, for example, because that energy will be produced by your movement,” said Sepulveda, whose research is funded by the National Science Foundation.

Electrical energy is created when the device is compressed by human motion. The completed device is as thin as a sheet of paper. The device used to power the LED lights was palm-sized, while the device used to power the touch screen was as small as a finger. Advantages such as being lightweight, flexible and low-cost could make it a promising and alternative method in the field of Mechanical-energy harvesting.

The device also becomes more powerful when folded. Sepulveda said, “You can start with a large device, but when you fold it once, and again, and again, it’s much smaller and has more energy. Now it may be small enough to put in a specially made heel of your shoe so it creates power each time your heel strikes the ground.”

Sepulveda and his team are also developing technology that would transmit the power generated by the heel strike to, say, a wireless headset.

1.Who is Nelson Sepulveda?

A. The major researcher in the project.    B. A professor of engineering.

C. The fund supplier of the research.    D. A journalist writing for Nano Energy.

2.The underlined word device in the 2nd paragraph is closest in meaning to ________.

A. keyboard    B. smartphone    C. screen    D. machine

3.From the passage we know that the nanogenerator ________.

A. becomes more powerful when kept flat

B. has already come into market in the USA

C. is lightweight and flexible though expensive

D. makes it possible to produce power by walking

4.The purpose of the passage is to ________.

A. persuade people to buy the device    B. bring in a new way to save energy

C. introduce a breakthrough in science    D. honor Nelson Sepulveda for his contributions