I would most greatful if someone could clarify why we say in reference to the past...<br/><br/>ON the morning OF May 20th, I went..... <br/><br/>(NB you can reverse the clauses and still have the same issue)<br/><br/>I went.... on the morning of May 20th<br/><br/>But when referring to a future event we change the prepositions<br/><br/>Will you meet me IN the morning ON MAy 20th?<br/><br/>Thanks very much<br/><br/>Stuart