Spanish language Q&A Forum

I was told in writing here in this app (and in another Spanish app) that when saying what you are (what your profession is), you do not put an article before the name of your occupation.  Example:  “Mi papá es médico.” (My dad is a doctor.) - No un of una.  I took a test here earlier today and someone is a carpenter.  I left out the article and was correct.  Did I miss an exception?  I will say that in this test, it was the person saying what their own profession is. “Yo soy un ?”  I’ve already forgotten what the job was.  Can anyone let me know?  Gracias. 

Does anyone know of a good free online language exchange?

I’m trying to unlearn or clarify some things about this verb. Could you comment on if these examples are correct or wrong and provide a short explanation? “A ti te gusta pollo?” “Me gusta pensar.” “Me gusta todo.” “Les gustan criticarme.” “A mi no me gustan ellos.” “Ellos no les gusta a mi.”

Entender means understand, but in this example: Ella entiende de arte. - means: She knows about art. Why?

Thank you so much!

I'm failing to see why 'aquel' was marked incorrect in the test question about my parents visiting that village. The sentence doesn't state or imply any distance, so surely either aquel or ese should be acceptable.