Bold answers
En la galería de arte, dudábamos que el artista pintara tantos cuadros en un año. Era imposible que el pintor pudiera terminar todos los cuadros de la colección en tan poco tiempo. No creíamos que él terminara todo el trabajo sin la ayuda de otros pintores. Era probable que sus estudiantes de arte ayudaran a crear algunos cuadros. Los expertos no estaban seguros de que las obras fuesen firmadas por el pintor.
Translation
In the art gallery, we doubted that the artist would paint so many paintings in a year. It was impossible for the painter to finish all the paintings in the collection in such a short time. We did not think he would finish all the work without the help of other painters. It was likely that his art students helped create some paintings. The experts were not sure that the works were signed by the painter.
Step-by-step explanation:
The subjunctive mode expresses doubt, possibility and hypothesis.
