I am so dead.
我累死了。/我死定了。
You are dead.
你死定了。

death 名词 死亡
dead 形容词 死的
die 动词 死
died 动词死的过去式

My cat is dead.
我的猫死了。
It died yesterday.
它昨天死的。
Its death was a surprise.
它的死真是一个意外的事情。

表达：
1.at death's doorstep
病的很重 / 灾难来临
He seems so sick that he is at death's doorstep.
他看上去病的很重，快撑不下去了。

2.sick to death of
厌倦某事
I am so sick to death of this bloody song.
我受够了这首歌了。

3.as dead as a dodo
过时了，不流行了
Although popular in the 1970s, disco music is as dead as a dodo today.
虽然迪斯科在70年代很流行，但是现在已经过时了。