There is no doubt that the earth is becoming warmer. But how has the phenomenon come about? All scientists subscribe to the view that it is because of human activity. Burning of fossil fuels has resulted in too much CO2 in the air and the temperature of the earth tends to go up with ‘greenhouse effect’. But some scientists are opposed to the point that quantities of CO2 are bad for the earth. Besides, even if people have done something to reduce CO2 , the earth keeps on being warm. Nobody knows the effects of global warming in the future.

A. be likely to B. take care of sb C. usually happen