The use of nuclear power has already spread all over the world. (1)_____, scientists still have not agreed with what should be done with the large (2)_____ of waste materials that (3)_____ to increase every year. Most waste materials (4)_____ of simply by placing them somewhere. But nuclear waste must be (5)_____ with great care. It (6)_____ dangerous radiation and it will continue to be (7)_____ for hundreds of thousands, even millions of years. How should we get (8)_____ of such waste material in such a way (9)_____ it will not harm the (10)_____? Where can we (11)_____ distribute it? One idea is to put this radioactive waste inside a thick container, which is (12)_____ dropped to the deep bottom of the ocean. (13)_____ some scientists believe that this way of (14)_____ nuclear waste could kill fish and other living things in the oceans or interfere (15)_____ their growth. Another way to (16)_____ nuclear waste is to send it into space, to the sun, (17)_____ it would be burned. Other scientists suggest that this polluting material be (18)_____ thousands of meters under the earth's surface. Such underground areas must be free (19)_____ possible earthquakes, and advances are being made. But it may still be many years (20)_____ this problem could be finally settled.