快速答案
último 表示顺序中的最后一个；passado 表示当前时间之前的一段时期。
可靠的方法是先判断这个词在句子里的功能，再翻译。
每个词的作用
último
last or final
Use último for the end of a sequence or the most recent item viewed from now.
passado
past or last
Use passado for a completed period before the present one.
如何选择
- último: Choose último if the sentence points to the end of a sequence or the most recent item viewed from now.
- passado: Choose passado if the sentence points to a completed period before the present one.
例句
Peguei o último ônibus.
I caught the last bus.
Viajei no ano passado.
I traveled last year.
常见误区
O último ano may mean the final year of a course or the most recent twelve months. O ano passado is the previous calendar year.
放到语境中练习
从你的真实生活中选一个句子，写两遍：一次用 último，一次用 passado。如果两个版本都可以，说明意思怎样变化。