Hi, I am in need of resolving an argument. Is it possible to use the word "if" in a sentence without indicating the else? For example: "If they are asleep." It leaves one wondering what is to happen to the sleeping persons, but is that acceptable? On its own it seems out of place, but if it were the response to a question ("Shall I kill them?") would it then be acceptable? And if so, what is the terminology for this arrangement (indicating the else in a different sentence/implicitly)? Finally, if the aforementioned sentence is correct, then would it also be correct to assign a semicolon in the following manner: "If they are alseep; they are fair game." It seems technically correct to me, but the use of a period/semicolon seems to disjoint the two sentances, and since they reference the same persons it seems unecessary and that a comma would suffice (treating the "they are fair game" portion not as its own sentence, but as something lumped into the else).

Hi guys,

"If they are asleep." In terms of formal grammar, I don't consider this to be a sentence. I'd call it a sentence fragment.

However, we certainly say this kind of thing all the time, everyday, in all kinds of contexts. I hope Forum readers do not think that native speakers always speak in precise and grammatically perfect sentences. We don't.

Best wishes, Clive
The following exchange is correct.

-- Shall I wake him?
-- If it's not too early.

It assumes the answer is Yes, wake him if it's not too early.
The omission of a group of words that can be understood from context is called ellipsis.
If it's not too early, on its own, is not a complete sentence, of course.

Note, however, that there is nothing here that involves an else (or its synonym, otherwise).
I think you are mistakenly calling the consequent of the if clause, "the else".

Here's the full structure -- all three clauses:

If it's not too early, wake him; else, let him sleep.

The part in blue is not the else clause; the part in red is the else clause.
The part in blue is called the consequent (clause), not the else clause.
The if clause in orange can also be called the antecedent (clause).

Do not separate the if clause from the rest of the sentence by a semi-colon. Use a comma.

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Normally if is added in a sentence when there is another clause connected with it to complete the sense
but 'if I would be a doctor' or 'if I could visit the place' these types of sentences are also used where the rest of the sentence/meaning is implied
"If they are alseep, they are fair game."
with a comma.
"If they are alseep, then they are fair game."
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