1 . They gave their lives in _________ (保卫，保护) of freedom. (根据汉语提示单词拼写)

2 . This produced a chain ________(反应), which made it possible for life to develop. （根据汉语提示单词拼写）

3 . The drug may prove to be an effective c__________ for brain cancer. (根据首字母单词拼写)

4 . The British and the Americans not only speak the same language but (also) share a large number of social __________ (风俗)．（根据汉语提示完成句子）

5 . The f_________ of the heart is to pump blood through the body. (根据首字母单词拼写)

6 . The students put the books on the library desk, and the l____________ checked them in.(根据首字母单词拼写)

7 . Keeping the right b________ (平衡)between progress and protection is a big challenge. (根据中英文提示填空)

8 . I find it hard to work at home because there are too many d_______ (分散注意力的东西). (根据中英文提示填空)

9 . What recreational f______ (设施) are now available? (根据中英文提示单词拼写)

10 . There is a full ________ (一系列) of activities for children. (根据汉语提示单词拼写)