小测验：选择正确的单词

1. People should preserve children from being hurt.
   人们应保护儿童免于受害。
2. Deep freezing is the simplest way of preserving food.
   深冻是保藏食品最简便的办法。
3. Tried to preserve family harmony.
   努力维持家庭和睦
4. He preserved his mask of solemnity even with acquaintances.
   他甚至和熟人交往也保持着一本正经的面孔。
5. It is difficult to preserve one's self-respect in that job.
   做那样的工作很难保持自尊.

　1个名词解释