To describe something as "dying" in Engpsh, you can use the verb "to be dying." For example:

"I'm dying of thirst." (meaning you are extremely thirsty)
"This plant is dying. It needs more water." (meaning the plant is not thriving and may not survive much longer)

If you want to describe someone or something as already dead, you can use the verb "to be dead." For example:

"The cat is dead." (meaning the cat has passed away and is no longer apve)
"The battery is dead. It needs to be replaced." (meaning the battery is no longer functioning and needs to be replaced)

It's important to use appropriate language and sensitivity when discussing death, as it can be a sensitive and emotional topic for some people.