If the sun has enough power to warm and light the whole earth, it must have enough powerto do other things, too. Can we use the sun’s plentiful energy to supply electricity, or at least toperform. the functions which electricity or other types of power usually perform? The answer isYES. For example, people have for many years been using the reflected（反射的）heat of the sunto cook. Solar（太阳能的）cookers have been built with several special mirrors reflecting the sunand centering its heat on the cooking part. This equipment can be used just like a gas or electriccooker: it is more expensive to make but it does not need any fuel, and so costs nothing to use. Another possibility of using solar energy is in house heating. The form. of energy we use must is electricity, and every day more is needed. But electricityalso has to be made, and to make it, huge quantities of fuel are required —oil, coal, gas and soon. The question which worries everyone today is: how long will these fuels last? Nobodyknows for sure, but most experts think it will soon be difficult to get enough electricity fromthese sources. It is possible that the sun can make a contribution here, too. Solar power has already been used to produce powerful heat. In Southern France a solarfurnace（锅炉）has been built, where temperatures reach more than 3000℃. This furnace is onlyused for experiments at present, but could be used to produce steam for a power station. So it is possible that one day in the near future we will depend on solar furnaces and powerstations to provide our electrical needs. Or perhaps each home will be able to use solar power forlighting and heating. According to Paragraph 1, the sun can provide electricity because ______. A.it gives us warmth B.it gives us brightness C.it has plenty of power D.it has plenty of gas One advantage of a solar cooker is that ______.A.no fuel is needed B.no mirror is needed C.no heat is needed D.no space is needed According to Paragraph 4, most experts think that fuels on the earth ______.A.are always available B.are limited C.are expensive D.are always useful The underlined sentence in Paragraph 4 means that the sun may provide us with ______.A.enough fuels B.enough steam C.enough oil D.enough electricity This passage is mainly about ______.A.the problems of solar energy B.the functions of solar power C.the use of house heating D.the forms of energy