1、词根精讲
FIN comes from the Latin word for "end" or "boundary". 表示end,boundary, 结束，范围
any of the thin parts that stick out from the body of a water animal and especially a fish and are used in moving or guiding the body through the water.
从源头上看，fin表示的是“鱼鳍；鱼翅”等尖细的物体。后来引申为“尖端,末端”；而末端是指一个事物的最后面，因此fin引申为“结束；最后”之意。
2、同根词汇
1. final: coming at the end:being the last in a series, process, or progress 最后的；最终的
例：the final chapter （最后一章） ；final exams（期末考试）
2. finalist: a person who competes in the last part of a competition: n 决赛选手 (final 最后的+ist人)
例：They interviewed all of the finalists before making a decision.
3. fine: a sum imposed as punishment for an offense 罚款。（罚款跟结束有什么关系呢？比如开车违规了，警察给你一张罚单，此时就算“fine （好了），事情也就fine（结束了）”）
例：The motorist had to pay a fine for speeding.
4. finale: the last part of something (such as a musical performance, play, etc.) n 结局，终曲(fin结束，最后+ale 表示音乐类→终曲)
例：He played a very difficult song for the finale.
5. finite: having limits a 有限的 (fin范围+ite 形容词后缀：有范围的)
例：a finite number of possibilities 有限的可能性
6. infinite: having no limits. a 无限的(in 无+fin范围，结束+ ite形容词后缀)
例：He has infinite patience when he's dealing with children. 他对待孩子，无比耐心。
7. confine: to put limits or boundaries around something. vt.限制，监禁（con加强语气+fin范围）
例：Dikes confined the floodwaters
8. define: to explain the meaning of (a word, phrase, etc.) vt限定;下定义(de 加强语气+fin限制→下定义，即限定范围)
Wang Jianlin defined "small target" as one hundred million.
王建林把一个亿定义为小目标。
