完形填空

　　Bears and humans often meet in National Parks．　　1　　 campers and hikers are warned not to feed the bears-many people ignore these warnings and feed the bears 　　2　　．When bears are used to people’s food-　　3　　 soon arise．Bears like to eat a large variety of things-both meat and vegetables．Without human assistance-bears live 　　4　　 on roots-twigs-leaves of trees-insects and small animals．With people 　　5　　-the bears’ tastes quickly 　　6　　 to include sandwiches-hot dogs-hamburgers-and anything else they can temp humans into 　　7　　．

　　Bears often 　　8　　 clever strategies(策略) for getting people to let go their food supplies．　　9　　-an unsuspecting(无戒备心的) hiker has taken off his or her pack for a rest only 　　10　　 a bear charge out of the woods-　　11　　 the pack and quickly disappear into the underbrush with it．Hanging the pack on the tree branch won’t 　　12　　．

　　Bears have been known to climb up-jump off-and catch the pack on the　　13　　 down．One mother bear stretched up with her baby on her shoulders to reach a pack stored on a pole．Many bears 　　14　　 people into giving up their supplies．Although a bear is 　　15　　 to attack a person and would probably run away 　　16　　 screamed at-few people are willing to do so．Most people 　　17　　 the pack and run the other way．This-of course-delights the bear．In some places-the Park Service installed(安装；设置) some metal barrels with lids to help campers keep their 　　18　　 safe from bears．Although the bears were unable to open these containers-the effort was 　　19　　 successful．Most campers-unable to 　　20　　 the metal drums from rubbish cans-never used them for the intended purpose．

(1)

(2)

(3)

(4)

(5)

(6)

(7)

(8)

(9)

(10)

(11)

(12)

(13)

(14)

(15)

(16)

(17)

(18)

(19)

(20)