You say:

1-Every time I drink coffee I get a stomach ache.

2-Should every time I drink coffee I get a stomach ache?

3-Should every time he drinks coffee he get a stomach ache?

4-Should he drink coffee he gets a stomach ache?

5-Should every time he drink coffee, he get a stomach ache?

I realize the word-order is slightly unusual, as 'every time' should come at the end of these sentences. Nevertheless it is syntactically correct.
The question is, then, which is correct 3's 'drinks' or 5's 'drink'?

Thanks--Email Removed
#3 sounds the best, although the word order in 2-5 is very confusing.

I say #3 because when I rearrange the words I get this:

"Should he get a stomach ache every time he drinks coffee?"

Still, why use "should" when you can use "does"?

"Does he get a stomach ache every time he drinks coffee?" sounds much, much better.
IMHO neither 3 nor 5 is correct. In these sentences 'every time' is redundant because 'should' implies 'every time'. The best one is 4. After 'should' the verb goes in infinitive (drink). However, the other verb (get) should have the present tense 's'.
By the way, the sentence is not a question, so the question mark shouldn't be there.
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It is a question. It may be rhetorical.

Should X happen to me every time I do Y?

Should I get arrested every time I commit a crime?
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I don't think the sentences refer to the 'morality'or 'advisability(??)' of getting a stomachache. I think the poster is referring to a type of inversion used with 'should'. It is similar to conditional clauses (usually with so-called first conditionals):
If I see him, I'll tell him you called = Should I see him, I'll tell him you called.

What about this one?
Everytime I go out without an umbrella, it rains. or
Should I go out without an umbrella, it rains.

It does sound rather strange to me, but I think this is the idea the original poster was getting at; 'should' meaning 'every time'.
What do you think?
i agree doubly with lib, both on his interpretation of the original post as well as his response that it sounds a bit stilted. (again, punctuation has caused the confusion ... the "poster" should not have put question marks after each sentence, just after his initial question!)
This is the original poster, Email Removed. Thank you all for responding.
Yes, 4 should not have had a question mark. But you all lost track of my original question. And I think I figured this one out. But before I congratulate myself on genius, please tell me this makes sense.
The problem is
1-Should he remember his country, he cries.
2-If he remembers his country, he cries.
3-Whenever he remembers his country, he cries.
These all mean the same thing. Namely, that they all mean ‘every time’.
So, to combine ‘every time’ in one of the sentences above confuses the sense of the sentence; unless a comma is added.
Whenever he remembers his country, he cries, every time.
This much is easy to figure out. The problem arose from the fact that “Should” has two senses: the conditional and the interrogative.
If you say,
Should this happen every time (an interrogative)
Should this happen (more likely a conditional).
Should every time this happen(s) (confused: this much was clear to your native ears, but not mine).
I think the rest is now clear. And again, thank you all.
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