1 . The magazine attracts a large number of __________(订阅者) by its unique content. （根据汉语提示单词拼写）

2 . He has spent all his life on the research and ______ (develop) of better rice plants. (所给词的适当形式填空)

3 . Mandela made a great ______ (contribute) to the equal rights of black people. (所给词的适当形式填空)

4 . He made lots of mistakes because of his ______ (care). (所给词的适当形式填空)

5 . What delighted the fans was that Tom performed well in the table tennis ________ (锦标赛). (根据汉语提示单词拼写)

6 . At some time in the past Yellowstone must have blown up with a ________ (violent) far beyond the scale of anything known to humans. (用所给词的适当形式填空)

7 . She wants a job that gives her more ______(responsible). (所给词的适当形式填空)

8 . The wild population of koalas is in danger of ______ (灭绝). (根据汉语提示单词拼写)

9 . Misunderstandings caused constant military f______ between the two countries. (根据首字母单词拼写)

10 . The past years have witnessed the sharp decrease in the number of whales. Consequently, experts are trying to save the whales from ______ (extinct). (所给词的适当形式填空)