Earthquakes may take place anywhere on the Earth's surface．（49） 　　，they are most probably to happen near mountains．

During an earthquake，the Earth's surface shakes．Houses fall，people are killed or injured，and （50） 　　whole cities are destroyed．

But we can do something to protect （51） 　　against earthquakes．Scientists have made maps （52） 　　the"earthquake belt"．In the belts，earthquakes are likely to happen．In these areas we can build （53） 　　houses to resist（抵抗）earthquake shocks．

In the future，scientists will be able to predict exactly （54） 　　earthquakes will take place．Then they can tell people to take measures．Thus lives can be saved and damage（损失）can be（55） 　　

49．A．But	B．However	C．So	D．And
50．A．sometime	B．sometimes	C．some time	D．some times
51．A．ourselves	B．themselves	C．itself	D．myself
52．A．shown	B．shows	C．showed	D．showing
53．A．large	B．small	C．special	D．empty
54．A．When and where	B．when and what	C．where and what	D．how and why
55．A．doubled	B．lessened	C．increased	D．added．