题目内容：

 

1.During the experiment, ____________(志愿者) were asked to sniff various pleasant smells and unpleasant smells.

2.By _________(分析) the structure of these sentences we learn more about English grammar.

3.All her hope was___________(毁坏) because of that failure.

4.The campaign is intended to raise public _____________(意识) of protecting our earth.

5.The bell ______________(显示) the end of the period rang, interrupting our heated discussion.

6.Jack and Max are twins. Seeing the two of them together c_________ me —I totally can’t tell one from the other.

7.While the students found the soldier’s idea interesting, the system was too difficult to be of p__________ use.

8.U____________, I won’t be able to attend the meeting.

9.In the 1950s the Chinese government introduced s____________ Chinese characters.

10.In memory of the Americans who died in the attack, a national m__________ was built in Pearl Harbor.