为什么leave用ing形式,

这是现在分词 作结果状语 ,与主语是主动关系所以用现在分词,再如
Football is played in most of the countries in the world,making it a popular game in the world.
Tom has passed the final exam ,making his parents very happyl.这两句中的making用的是现在分词做结果状语,且表示必然的结果.如果是偶然的结果用不定式.如
He hurried to the station,to find the train had gone.发现这个动作是主语没有想到的所以是偶然的.用不定式.这是英语中两种结果状语的典型题.