year after year 与year by year都作有区别吗

　　意思有区别。
　　year after year：年复一年地；每年；一年又一年； 穷年累月。强调时间周而复始。
　　year by year：逐年；年年； 一年一年地； 逐年地；年轮。有递进的意义。
　　Some bulbs produce flowers year after year.
　　一些鳞茎植物每年都会开花。
　　If they hurt you before, why let them keep doing it year after year in your mind?
　　如果他们曾经伤害你，为什么还年复一年地让他们在你的心灵中继续为害？
　　The output is increasing year by year.
　　产量逐年上升。
　　Since production has risen steadily, the personal income of the commune members has increased year by year.
　　由于生产不断发展， 社员们收入逐年增加。
　　After years of stagnation, the malaria situation, especially in Africa, is looking better and brighter year by year.
　　经过多年停滞，疟疾防治工作，特别是在非洲，现似乎在逐年加强和改进。

　　year after year跟year by year的区别在于，前者表述的过了一年又一年，后者则表述的是一年接着一年。
　　year after year，形容时间很长，或者说等待的期限很长。year after year，侧重结果。
　　year by year，则形容持续等待，等了一年一年又一年，过了一年又一年，持续的过程很难熬。year by year，侧重过程。