That is a very big subject. What has your own research told you?
Student or Learner
what is the rule to use on, in, at?
Welcome to the forum, Dora.
Please note my corrections to your post. Start every sentence with a capital letter, as you do in Spanish.What are the rules for using 'on', 'in', and 'at'?
Compare these three prepositions with their Spanish equivalents. Ask us about any specific problems you have in their usage,