die / died / dead

Die is the verb in the present, and died is the verb in the past:

He’s very sick; the doctors say he’s going to die.

The nurse comforted the dying soldier.

One of the country’s most famous authors died last week.

Dead is the adjective, so we often use it with the verb “to be,” or before a noun:

He died in 1972. He has been dead for over 30 years.

The victim was dead by the time the ambulance arrived.

I found a dead rat under my bed.

Police discovered a dead body in the basement of the old building.

Informally, we can also use die/dead when an electronic device stops functioning, or when a phone or internet connection gets disconnected:

I need to recharge my cell phone. The battery’s dead.

My laptop died and the computer repairman said he can’t fix it.

Before I could ask my question, the line went dead.

(the telephone connection got cut off)