According to one belief, if truth is to be known it will make itself ap parent, so one ______ wait instead of searching for it.

It is during （） that work energy is being put into the engine; during the other 3 strokes of the piston, the engine is having to do the work.

A hydraulic machine is one that uses （） to do work.

Food alone is not the（）of energy.

______ can make a mistake; no one is perfect.

_____ can make a mistake; no one is perfect.

The scale of the energy is one to ten.____

For the duties assigned in the muster list, one person may do more than one work and one work may be done by more than one person.（）

You are working on the cost budget for one project. Which of the following is true（）

Besides climate change, developing countries like China need to deal with energy【21】and environmental issues: the development of sources of clean energy needs to be【22】line with their interests. Clean energy has been given greater prominence than ever before; it is seen as a new industrial【23】and【24】of economic growth for the new century. The time for clean energy has come.In China, clean energy is moving ahead at full speed. Take wind power as an example: by the end of last year, China had【25】wind power generating capacity of 12. 21GW, making China the largest wind power generator in Asia and fourth in the world. But according to the research, one-third of wind power capacity is running【26】due to an inability to get the power to the national【27】.India-like China—relies【28】on coal for its energy needs. This will only change if the funds and technology to develop clean energy, such as wind and nuclear power, are【29】. India will not choose clean energy【30】. Nuclear power is currently the most【31】of clean energy sources.【32】, if it is to be【33】on a large scale by developing nations, technological advances will be needed to make it competitive with coal.Compared【34】developed countries, developing countries have more【35】choices when it comes to energy structure. Promoting economic growth requires【36】energy—and coal, the cheapest and most【37】source of energy for many countries—is the【38】choice. Cheap coal means cheap electricity and a competitive economy. Rising electricity prices would cause public【39】and impact on standards of【40】.(21)