They have the same endings except in the nosotros and vosotros forms.
You have to include the rules with the question
I would say the main headings and key concepts in a reading assignment would help one to grasp what the topic is basically about ie paying attention to these two things would be an essential part of a study guide so that the main meaning of the writing could be grasped.
A primary source is where the information comes directly from the original copy or someone who experienced it first hand, and where as a secondary source is someone or something that was not there when the event took place- hope this helps!!
