This worksheet is intended for intermediate to advanced students for listening (listening for detail) and speaking practice, but also some general knowledge. It uses the video by Bill Nye the Science Guy about electricity. To prepare students for that, you can elicit names of household appliances and other electrical devices they use and ask if they know how it happens that they are powered (I was doing the worksheet just after Christmas, so I used Christmas tree lights to demonstrate the question). First, provide vocabulary and listen without questions; then, give questions and listen again for detail. Have fun!