Fill in each blank with one suitable word.

Energy is one of the problems that many people are interested in. It is not an unfamiliar word. It is heard, said, discussed day after day. It is close to everyone’s (36)_____ life. You turn on the lamp and it is (37)______ that gives you light. You turn on a TV and it is energy that gives you pictures and sound. You ride a motorcycle and it is energy that gives you movement. You (38)______ your meals and it is energy that gives you heat to boil rice.

The problem is that the demand for energy is rising and that the price of energy is getting (39)______ and higher. The supply of energy on earth is limited. It cannot provide us all forever. The shortage of energy in the future is inevitable. Therefore, (40)______ energy is a must if we want to continue to live in a safe and sound world.