In educated 19th and early 20th century England, Harry would probably have replied "I?"
Here's an example.
Sir Bash. Confess the truth ;- have not you been listening and overbearing my conversation?
Side. Who, I sir? Not I, sir.
The Way to Keep Him: A Comedy, in Five Acts By Arthur Murphy 1925
These days it sounds ...
Jealous would indeed fit, even if he trusts her.
Possessive could fit.
Proprietorial is also very fitting. Defined as: behaving as if one owned a particular thing or person; possessive.
Depending on the intensity of the emotion, the person may simply be wary.
Jealousy has many meanings, and many people often disagree with each others' meanings. The word has ...
 Does this work?
 Yes, that works.
In a clause like  the dummy auxiliary verb "do" is used to form the interrogative, and it's this verb that is marked for tense and person ("do/does/did"). It's not possible to have two tensed verbs in the same verb phrase, so the complement of dummy "do" must be the unchanging plain (...
I don't know what this phenomenon is called nor what the rule is.
It is called "question formation in English"
It is absolutely standard. When you have a 'helper' verb, the helper verb is conjugated and the main verb keeps its infinitive form.
Here are the rules:
Question formation in English is different from the formation of other sentences in ...
You can say either, but they have slightly different nuances.
My old popcorn maker is not heating up.
is not necessarily comparing anything, unless you've previously established that there are two popcorn makers. This can be used when you have only one popcorn maker, and "old" is simply being used as an adjective to describe it. In that case, it'...
In your context, an ordinal is a position: you can ask "which" or "where."
A: “I was the first in the queue.” B: “Which position [were you in the queue]?”
D: “What was your position in the queue? E: “I was the first in the queue.”
F: “Where were you in the queue?” G: “I was the first in the queue.” (This works if both know the context.)
First, it depends on the language. Like German go Italian ("Io?" not "Μe") and Greek ("Εγω?)". But French goes with English ("Moi?" not "Je"?). Well, I'm cheating a bit, because 'moi' is not not exactly the object form. It is rather the indirect object form (as in "donnez le moi", or "Ce ...
Let me first say (1) in "it is me.", "Me" is the dative, not the accusative,
S. Nom. ic, gen. min, dative me, accusative mec.
Pl. Nom. we, gen. user, dative us, accusative usic.
(2) The answer is "because the French say it that way."
English grammar usually agrees with German.
The war for It is I as ...
Yes, they are grammatically incorrect, because the are sentence fragments. However, I wouldn't call them "wrong", because there is no rule that says that the titles of the questions in stack overflow have to be 100% grammatically correct. They get the poster's meaning across in a clear and concise way.
These are not questions. These are relative infinitives, like what to order, who to tell, when to leave, or which one to pick. Putting a question mark after them does not make them questions. Relative infinitives are often used in lists, like journalists' bullet points: what, where, when, how, who, why, ..
They can be used as embedded question complement ...
It's the difference between a main clause and a content clause, and a tensed vs infinitival interrogative construction.
Interrogative main clause :
How does one list files in a directory in C?
Interrogative content clause:
Please tell me how one lists files in a directory in C.
The subordinate clause above is tensed - it has a a primary verb form.