When a strong earthquake occurs on the ocean floor rather than on (36)__________ , a tremendous force is (37)_____ on the seawater and one or more large, destructive (38)____ called tsunamis can be formed. Tsunamis are commonly called tidal waves in the United States, (39)________ this is really an inappropriate name in that the (40)______ of the tsunami is an underground earthquake rather than the ocean’s (41)_________ . Far from land, a tsunami can move through the wide open vastness of the ocean (42)____ a speed of 600 miles (900 kilometers) per hour and often can travel tremendous (43)____ without losing height and strength. When a tsunami reaches shallow coastal water, it can reach a (44)_________ of 100 feet (30 meters) or more and can cause tremendous flooding and (45)_________ to coastal areas. 36. a. land b. ground c. earth d. soil 37. a. installed b. exerted c. exhausted d. struggled 38. a. currents b. streams c. waves d. tides 39. a. therefore b. and c. for d. but 40. a. cause b. reason c. effect d. force 41. a. surface b. tides c. waves d. water 42. a. in b. with c. for d. at 43. a. trips b.journeys c. distances d. spaces 44. a. length b. height c. strength d. weight 45. a. damage b. harm c. ruin d. spoil