You have to use the -ed form because that describes how he felt. Using the word excruciate as a transitive verb is rather uncommon, possibly archaic, but it is "legal" according to Webster's Third. It means to torment someone; to cause someone intense pain and suffering, etc.
So the possibility, whatever it is, is causing him great pain and suffering.
The -ing form would describe something that makes you feel intense pain, or the intense pain itself.
Ex. When I dislocated my shoulder, the pain was excruciating. It was an excruciating injury.
The fundamental difference between -ed and -ing adjectives can be loosely summarized as follows:
*An -ed adjective describes your condition or how you feel.
*An -ing adjective describes the thing that did that to you or that made you feel that way.
Ex. This is a boring movie; I'm bored. (That is, it's starting to make me feel bored.)
Ex. This is an exciting basketball game! I'm excited! (That is, it's making me feel excited!)
I wish I had NT$10 for every time I heard someone here in Taiwan say, "I feel so boring."
Could any one explain to me the following sentence.
I stand here, excruciated by the possibility.
Why use excruciated instead of excruciating??
what's the correct grammar and why?
Thank you very much
One reason this sounds odd is that the verb "to excruciate" is seldom used.
But other verbs are used in just that way:
> "I stand here, excited by the possibility."
(but not "exciting by the possibility")
> "I stand here, overwhelmed by the possibility."
(but not "overwhelming")
> "I stand here, transfixed by the possibility."
(but not "transfixing by the possibility")
All these past participles are formed from the use "TO BE (verbed)"
To be excited by
To be overwhelmed by
To be transfixed by
In all of these cases, the "actor" is "the possibility," not "I"
"I" am not exciting anything -- the possibility is exiting ME --
so "I am excited"
I am not overwhelming anyone -- the possibility is overwhelming ME --
so "I am overwhelmed"
I am not transfixing anything -- the possibility is transfixing ME --
so "I am transfixed"
These are all transitive verbs, and the person has been the object of their action:
The possibility excited me.
The possibility overwhelmed me.
The possibility transfixed me.
So the person is "excited, overwhelmed, transfixed, excruciated"
In other cases, the present participle would be correct:
I stand here, laughing at the possibility.
I stand here, mulling over the possibility.
I stand here, dreaming about the possibility.
The difference is that in all of these cases, "I" am the one doing the action; it is not being done to me.
These are intransitive verbs, and the person is doing the action, not "the possibility":
I am laughing at the possibility
I am mulling over the possibility
I am dreaming about the possibility