after a long time or some difficulty

We finally got home at midnight. 我们终于在午夜时分到了家。

After months of looking he finally found a job. 在找了好几个月之后他终于找到了一份工作。

used especially at the beginning of a sentence to introduce the last point or idea

Finally, I'd like to thank everyone for coming this evening. 最后，我要感谢各位今晚光临。

in a way that will not be changed

The plan hasn't been finally approved. 计划还没有获得最终批准。