快速答案
demorar 表示所需时间长短；atrasar 表示晚于计划或截止时间。
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
demorar
to take a long time
Use demorar for an action requiring time or someone being slow to arrive.
atrasar
to delay or be late
Use atrasar for moving something past its scheduled or expected time.
如何选择
- demorar: Choose demorar if the sentence points to an action requiring time or someone being slow to arrive.
- atrasar: Choose atrasar if the sentence points to moving something past its scheduled or expected time.
例句
O conserto demorou duas semanas.
The repair took two weeks.
O trânsito atrasou o ônibus.
Traffic delayed the bus.
常见误区
A trip can demorar três horas and still not be atrasada if three hours was the planned duration.
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 demorar，一次用 atrasar。如果两个版本都可以，说明意思怎样变化。