Prepositions are a grammar topic that require a degree of focused practice. Exposure to correct structures and acceptable uses is not usually enough for mastery. Recently I helped students understand when and why more than one word order is possible with indirect objects. We discussed phrases like giving someone an explanation and giving an explanation to someone.
If you think it would be helpful to call attention to such variations and how the position of the indirect object can change the focus, please share my Prepositions TO and FOR_Word Order_handout with your upper level students.
You might also consider another handout I shared in a previous post: Pondering the Placement of Prepositions.