at last，at length，eventually，finally，in the end，lastly
这些词或词组均含有“最后，终于”之意。
at last 多指经主观努力，克服各种困难后才终于达到目的。
at length 强调经历一段长时间后终于完成，侧重在时间部分。
eventually 侧重于动作或行为的结果。
finally 常与at last换用，都可用于对往事的描述，但finally不带感情色彩，指一系列事情的最后结局。
in the end 与at last同义，但in the end不仅可指“过去”还可表示对“未来”的预计。
lastly 指连续顺序的最后，通常用在列举事情的场合。
参考例句
1. She finished the third thing eventually, and the most difficult thing. 她终于完成了第三件事，也是最困难的一件事！
2. One secondary spermatocyte divides and eventually grows into two sperm cells. 一个次级精母细胞分裂并最终产生两个精子。
3. Eventually she went back to her father solely because there was no other way. 最后，只是因为实在没有别的办法了，她才回头去找她爸爸。
英英解释
adv.
1. within an indefinite time or at an unspecified future time
2. after a long period of time or an especially long delay
