Question

Los ladrones fueron detenidos por la policía ayer por la noche.


Why is it "fueron"?
I think estar is more appropriate. It is a "state."

Answer 1

Let me translate this for you:

The thieves spend last night in jail because of the police.

Now, I am not sure how to explain to you why it makes more sense to say "fueron", let me call @esshotwired . :}

And I am extremely sorry that someone did not answer your question earlier. Thank you for choosing OpenStudy, though. :)

Answer 2

Hmmm... why me though? You never leave out any detail.

Answer 3

It is fueron because it is plural and it is past.
It can't be estar because it is the verb to be, it is singular, and it doesn't work because it also says ayer, and ayer is past.