After working for a long time,.但为什么是Having working for a long time.

After working for a long time,.但为什么是Having working for a long time.
After working for a long time,.但为什么是Having working for a long time.

After working for a long time,.但为什么是Having working for a long time.
没有Having working for a long time.
只有以下两个：
Having worked for a long time.
Having been working for a long time.
这种用动名词开头的句子很多的.

因为吧
你已经work了 完成那段work了

因为for是介词..后面加动词要用现在进行时`