解释同上 例The Olympic Games was held in this city.This city held the Olympic games. 改为从句This is the city in which the Olympic Games was held.This is the city which held the Olympic Games
答:先行词+(介词+which to do sth. )=先行词+[介词+which 主语 (can/could) do sth.] 类例:The professor can hardly find sufficient grounds on which to base his argument in favor of the new theory.