完形补文。【Crude Oil】Although crude oil is still vastly (vast) available in the earth, it is not a / an__________(finite) resource. At some point it will finally be___________(exhaust). The demand for crude oil has increased by gigantic proportions. However,___________( discover) of new oil fields and investing in the oil industry have helped keep up with the____________(increase) demand for oil. The crucial question is, how long will the oil resources last?
__________(advance ) technology has made drilling oil more___________(effect) and efficient. With the aid of new methods it is possible to draw almost 65% of the oil as opposed to the old metnods. More____________(invest) have also made the drilling of oil well more effective. Currently most________________(transport) is dependent on oil and many industries are born out of or lean on byproducts of petroleum. Although alternative sources of energy are now _________(apply) , like solar and wind energy, it is still a long way to be completely_____________(dependent) of crude oil.