1 . Researchers at CU Boulder have developed a wearable device that changes the human body into a biological battery. The device is stretchy(弹性的) enough that you can wear it like a ring, sport band or any other thing that touches your skin. It also taps into a person's natural heat-employing thermoelectric generators to change the body's internal temperature into electricity. "In the future, we want to be able to power your wearable electronics without having to include a battery," said Jianliang Xiao, an associate professor at CU Boulder.

The concept may sound like something out of The Matrix film series, in which a race of robots have enslaved humans to harvest their precious organic energy. Xiao and his colleagues aren't that ambitious: Their devices can generate about 1 volt (伏特) of energy for every square centimeter of skin space-less volt per area than what most existing batteries provide but still enough to power electronics like watches or fitness trackers.

Scientists have previously experimented with similar wearable devices, but Xiao's is stretchy, can heal itself when damaged and is fully recyclable-making it a cleaner alternative to traditional electronics. "Whenever you use a battery, you're depleting(消耗) that battery and will, eventually, need to replace it," Xiao said. "The nice thing about our device is that you can wear it, and it provides you with constant power."

Just pretend that you're out for a jog. As you exercise, your body heats up, and that heat will radiate out to the cool air around you. Xiao's device captures that flow of energy rather than let it go to waste. "The thermoelectric generators are in close contact with the human body, and they can use the heat that would normally be sent into the environment," Xiao said.

1. What does Xiao expect of his device at present?

A．It will be used for medical purposes.

B．It will be made smaller and wearable.

C．It will change natural power into electricity.

D．It will supply constant power to wearable devices.

2. Why does the author mention The Matrix series in the text?

A．To give an explanation.	B．To make a comparison.
C．To introduce a topic.	D．To analyze the cause.

3. What does the third paragraph mainly talk about?

A．The strengths of Xiao's device.

B．The convenience of using a battery.

C．The replacement of wearable devices.

D．The development of traditional electronics.

4. What do we know about Xiao's device from the text?

A．It operates with plenty of power.

B．It is designed for practical use.

C．It benefits people's health in a way.

D．It's based on traditional electronics.