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However he studied hard, he failed the exam.

However he studied hard, he failed the exam. IfIf I rewrite this sentence by using "Although""although", is it necessary to put "very" in the "Although"although sentence"? e.g: Although he studied very hard, he failed the exam.

Although he studied very hard, he failed the exam.

However he studied hard, he failed the exam. If I rewrite this sentence by using "Although", is it necessary to put "very" in the "Although sentence"? e.g: Although he studied very hard, he failed the exam.

However he studied hard, he failed the exam.

If I rewrite this sentence by using "although", is it necessary to put "very" in the "although sentence"?

Although he studied very hard, he failed the exam.

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However he studied hard, he failed the exam. If I rewrite this sentence by using "Although", is it necessary to put "very" in the "Although sentence"? e.g: Although he studied very hard, he failed the exam. Thank you so much.

However he studied hard, he failed the exam. If I rewrite this sentence by using "Although", is it necessary to put "very" in the "Although sentence"? e.g: Although he studied very hard, he failed the exam. Thank you so much.

However he studied hard, he failed the exam. If I rewrite this sentence by using "Although", is it necessary to put "very" in the "Although sentence"? e.g: Although he studied very hard, he failed the exam.

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Sentence transformation

However he studied hard, he failed the exam. If I rewrite this sentence by using "Although", is it necessary to put "very" in the "Although sentence"? e.g: Although he studied very hard, he failed the exam. Thank you so much.