Turn this distinction into automatic recall
Falando teaches Brazilian Portuguese through grammar, vocabulary, audio, examples, and spaced review, so confusing pairs stop feeling like guesses.
Quick answer
A princípio looks back to the beginning. Em princípio states what is true in theory or as a general rule.
A reliable test is to identify the job of the word before translating from English.
What each word does
a princípio
at first or initially
Use a princípio for what happened or was believed at the beginning of a sequence.
em princípio
in principle or theoretically
Use em princípio for what should be true as a general rule, before practical details are checked.
How to choose
- a princípio: Choose a princípio if the sentence points to what happened or was believed at the beginning of a sequence.
- em princípio: Choose em princípio if the sentence points to what should be true as a general rule, before practical details are checked.
Examples
A princípio, ninguém percebeu o erro.
At first, nobody noticed the error.
Em princípio, o acordo pode funcionar.
In principle, the agreement can work.
Common trap
If inicialmente fits, use a princípio. If em tese fits, use em princípio.
Practice it in context
Pick one sentence from your real life and write it twice: once with a princípio, then once with em princípio. If both versions feel possible, name the meaning shift.
Turn this distinction into automatic recall
Falando teaches Brazilian Portuguese through grammar, vocabulary, audio, examples, and spaced review, so confusing pairs stop feeling like guesses.