Fejl i SQL-sætning

HVad er der galt med denne SQL?
Jeg har prøvet at skrive Response.Write (SQL)

SQL = "UPDATE Arranger SET Content = '" & Content & "', SET Headline = '" & Hl & "', "
SQL = SQL & "SET Author = '" & Author &"', SET StartTime = '" & strTime & "', "
SQL = SQL & "SET Place = '" & Place & "', SET City = '" & City &"', "
SQL = SQL & "SET Street = '" & Street & "' WHERE id= " & id & ";"
con.execute( SQL )