18:13 Feb 8, 2011 

"Most of their interpretations will coincide with what the artist intended when they are grounded by evidence from the picture."
I would then keep the same structure but add "they are" to clarify and avoid ambiguity.

19:52 Feb 6, 2011 

You might be right. However, to me, "what the artist intended when grounded by evidence from the picture." may look as artist=subject & grounded=verb, so it looks confusing. Fortunately, it is clear to me now. Thanks for your help.

19:33 Feb 6, 2011 

As a native English-speaker, it never ocurred to me that the subject of 'grounded' could be anything other than the 'students' (or, more precisely, the 'students' intepretations'). And your version, putting the 'grounded' phrase at the beginning, would, I fear, have sown doubts in my mind about the nativeness of the author.

19:21 Feb 6, 2011 

Gracias a sus colaboraciones me di cuenta que estaba leyendo la oración mal, confundiendo el sujeto de la frase en cuestión.Yo tenía una confusión de sujeto, por eso no me cerraba. La frase es "Most of their interpretations will coincide with what the artist intended when grounded by evidence from the picture."
Pero para evitar esta confusión, yo la hubiera escrito "When grounded by evidence from the picture, most of their interpretations will coincide with what the artist intended." Recién ahora lo veo.

Gracias. Varios ojos ven más que dos. :)