][ Can "INDIFINITE "be DOUBLED in the same statement][

[اوديسا]

Do we need "double indefinite article "an, a" in the following statements or can be omitted? Make it as a rule! Besides, which one is syntactically and semantically acceptable?

Examples

Is that an expression or an idiom

Or

Is that an expression or idiom

Or

Is that expression or an idiom

Or

Without

Is that expression or idiom

[motr]Thank you & Salam in advance[/motr]

[Brilliant Shores]

Welcom bro

the first statement is the right one

because it's a question so making balance is very important

both has to be singular by adding the articles

[اوديسا]

the first statement is the right one because it's a question so making balance is very important both have to be singular by adding the articles

Is that an expression or an idiom

We do use (aforementioned determiner) bef. a singular noun that has a plural form & initial vowel sound. Besides, words that begin W/ an unstressed "h". However, as you know that pronunciation can change what has been mentioned before. This thread really did raise many questions that did remind me the right use of determiner "an". Finally, as you said that a parallel is extremely important! Your explanation is excellent & insightful! Much appreciated & keep in touch