木门框的上帽头与门框挺的连接，常用______。A．单榫 B．双榫 C．双夹榫 D．

阅读短文，然后在下面的表格中完成内容提要，每空不超过3个单词。（共4个小题，每小题2分）
New Energy in the Twenty-first Century
Energy from the wind
Wind is a kind of clean energy, and there is lots of it, But, if there’s no wind, there is no wind energy.
Energy from the water
When water moves from a high place to a lower place, it can make electricity(电）without pollution. However, people have to build dams(水坝) to use this energy, and building dams is very expensive.
Energy from the earth
There is heat in the rocks under the earth. Scientists use the heat to make geothermal(地热的)energy. This kind of energy is cheap, but itis only possible in afew places in the world.
Energy from the sun
Solar panels (太阳电池板) on the roofs of houses can turn energy from the sun into electricity. Solar power is clean and plentiful(丰富的).but when the weather is bad, It doesn’t work.
New Energy in Twenty-first Century

	Advantages	Disadvantages
Wind Energy	Clean .There is a lot.	It needs 小题1:
Water Energy	小题2:	It is expensive.
Geothermal Energy	小题3:	only possible in afew places
Solar Energy	Clean and plentiful.	It depends too much on小题4: