1.my parents _ in their house for forty years.

1.my parents _ in their house for forty years.
a.are living b.live c.lived d.have lived
为什么不选a呢?现在正在住,住了40年.
2.-what's wrong with you coat?
-just now when i wanted to get off the bus ,the man next to me _ on it
a.sat b.had sat c.had been sitting d.was sitting
为什么不选a,一般过去时除了表过去经常重复的动作,还可表示过去时间内发生的动作或存在的状态呀!eg:the thief entered the buiding a few minutes ago