[Grammar] She was a teacher.../She had been a teacher

[Canarinho_Verde_Amarelo]

Hi everyone!

I was doing some exercises about Simple Past/Past Perfect, and a doubt has popped up. Which one of these sentences are correct?
1. She was a teacher before she became a journalist.
2. She had been a teacher before she became a journalist.


According to grammar rules, both of them are acceptable or only one must be chosen?


Thanks for your attention!

 

[bhaisahab]

Both are acceptable.

 

[Matthew Wai]

I think only 'had been' would be correct if 'before' was replaced with 'when'.

 

[Matthew Wai]

Would the meaning be different if 'was' was used instead of 'had been'?
She was a teacher before she became a journalist, but she might be not a teacher when she became a journalist.

 

[Canarinho_Verde_Amarelo]

As far as I could make out, both are acceptable according to grammar rules, despite different meanings between them. Nevertheless, what is the real meaning of each one?

As for conjunctions, how "when" and "by the time" could change the interpretation of these sentences, in case of replacement of "before"?

 

[Matthew Wai]

She was a teacher before she became a journalist, and she was a journalism student when she became a journalist.
'She was a teacher before she became a journalist' does not necessarily mean that 'She was a teacher when she became a journalist'.

Is that possible?