快速答案
比较巴西葡萄牙语中的 alterar vs. modificar：何时使用每个词，以及要避免的常见错误。
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
alterar
to alter or change
Use alterar for changing data, plans, settings, texts, or a state.
modificar
to modify
Use modificar for making modifications, often to structure, design, wording, or form.
如何选择
- alterar: Choose alterar if the sentence points to changing data, plans, settings, texts, or a state.
- modificar: Choose modificar if the sentence points to making modifications, often to structure, design, wording, or form.
例句
Preciso alterar meu cadastro.
I need to change my registration.
Modificamos o projeto inicial.
We modified the initial project.
常见误区
In forms and settings, alterar is often the normal interface verb.
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 alterar，一次用 modificar。如果两个版本都可以，说明意思怎样变化。