Hi

The expression "try again and again" seems more logical to me than "try, try again". I think the former is not considered correct or at least is not considered idiomatic. And perhaps the latter is little 'ungrammatical' but considered idiomatically correct. What is your opinion on this? Please let me know. Thank you.
The former is correct in normal speaking. The latter is more of an expression of its own. Choose the one you want.
Yes, the latter is the tag of a proverb or sorts: 'If at first you don't succeed, try, try again.' I found this:

IF AT FIRST YOU DON'T SUCCEED, TRY, TRY AGAIN. Don't give up too easily; persistence pays off in the end. The proverb has been traced back to 'Teacher's Manual' by American educator Thomas H. Palmer and 'The Children of the New Forest' by English novelist Frederick Maryat (1792-1848). Originally a maxim used to encourage American schoolchildren to do their homework. Palmer (1782-1861) wrote in his 'Teacher's Manual': 'Tis a lesson you should heed, try, try again. If at first you don't succeed, try, try again.' The saying was popularized by Edward Hickson (1803-70) in his 'Moral Song' and is now applicable to any kind of activity." From "Random House Dictionary of Popular Proverbs and Sayings" by Gregory Y. Titelman (Random House, New York, 1996, Page 154).
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Mister MicawberPalmer (1782-1861) wrote in his 'Teacher's Manual': 'Tis a lesson you should heed, try, try again. If at first you don't succeed, try, try again.'
Excuse me, but aren't all the quotation marks above suposed be double quotation marks?

Like "Teacher's Manual":"Tis a lesson you should heed, try, try again. If at first you don't succeed, try, try again"?

That's what I was taught.
Nowadays (in the Keyboard Era) many of us, including the author excerpted above, use single quotes for double quotes (thus saving a key stroke). For formal work, use the double ones as you were taught.
Mister MicawberNowadays (in the Keyboard Era) many of us, including the author excerpted above, use single quotes for double quotes (thus saving a key stroke). For formal work, use the double ones as you were taught.
To SAVE one more stroke? There's actually a specific key right on your keyboard for double quotes, which you don't have to strike twice to type the double quotes out! And that author used single quotes in his book? Seriously? Isn't the book supposed to be formal? It's the "Teacher's Manual"!Emotion: thinking
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Relax, chivalry. You'll pop a blood vessel, and we're not insured.
I've noticed in new novels that I've read recently that the use of single quote is used even in dialogues. Not worth worrying about, as far as I'm concerned.
chivalry
Mister Micawber It's the "Teacher's Manual"!
Back in the Middle Ages when I was in school, we underlined the title of a book. Nowadays the option is to use Italics.
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