Grammar

 

Well, it should be either grammar or vocabulary. But taking into account that only the structure is to be tested here, I �d go for grammar; vocabulary would a good option if the preposition somehow added meaning, but here changing the preposition doesn �t change the meaning of what �s being said (as it might be the case in "talking to something / someone - talking to an answering machine / talking to Jane" vs. "talking about something / someone - talking about the new answering machine / talking about Jane").

If your question asks students to use any prepositions  that may affect the meaning of the sentence, try to make sure they do not outnumber the questions in which that is not the case. If they do outnumber them, then you might consider the section "vocabulary"

Anyway, make sure you have no spelling mistakes that may confuse your students - your example is an incorrect sentence precisely because of that (I suppose you meant to type "She is ashamed  ..... herself", that �s the only possible option here).

 

Sandra