Listen to part of a talk about how solar panels work. – Luyện nghe VSTEP Part 3 – Bài nói, bài giảng

1. What are most solar cells made from?

A. glassB. copperC. siliconD. plastic

2. What does sunlight do inside a solar cell?

A. It charges a battery directly.B. It knocks electrons loose.C. It turns a small motor.D. It heats water.

3. What is the inverter for?

A. changing the electricity into the type used in homesB. storing electricity for the nightC. measuring sunlightD. cleaning the panels

4. Why do many people add a battery?

A. to make the panels last longerB. to reduce the cost of the panelsC. to work on cloudy daysD. to use electricity from the day in the evening

5. What does the speaker say about cleaning solar panels?

A. They should be cleaned by an engineer.B. Rain usually keeps them clean enough.C. They cannot be cleaned.D. They must be washed every week.