记忆法:
pre 在...之前 + serv 保留 + tion 构成名词 -> 提前保留 -> preservation 保留
n. 保存，保留The paintings were in an excellent state of preservation.
这些绘画保存得非常好。
The central issue in the strike was the preservation of jobs.
罢工的核心问题是工作职位的保留。
The widow's gratitude for her preservation was outspoken.
这位寡妇将保全自己的感激之情一吐为快。
