has dead是什麼時態

例句：

Her father will have been dead for 10 years by Octobor this year.

到今年十月份，她的'父親已經去世10年了。

Had he been taken to the hospital in time, he would have been dead!

要不是被及時被及時送到醫院，他早就死了。

I'm conducting an investigation, but all my leads have been dead ends.

我說，“我展開了調查，可是所有的線索都沒有結果。”

The Mesopotamian civilisations, not matter how long ago they started, have been dead for a long time.

不管兩河文明起源於多久，很久就已經消亡了。