1. She was drying her hair with the hair drier.

2. Dry your body with this big towel.
3. After bath, you need to keep your body dry not to catch a cold.

4. Study hard, and you will get high scores.
5.Practice ping-pong hard, or you will lose the game.

6. Work hard, and you will earn more money.
7. Work hard, or you will become poor.

8. Exercise hard, and you will become an excellent bodybuilder in the future.
9. Exercise hard, or you will become a patient.

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Would you check the sentences? Correct errors, please.

1 and 2 are okay. I might say, "Dry yourself with this big towel", but yours is fine. 3, "After YOUR bath" or "After a bath" 4, 5, 6, 7, 8 and 9: the commas are not necessary. The conjunctions "and" and "or" connect the independent clauses, so no punctuation is needed. If you wrote, "Study hard; you will get high scores" the semi-colon would connect the two independent clauses without the words "and" or "or", etc.

1. She was drying her hair with the hair dryer. (No error)

2. Dry your body with this big towel. (No error)
3. After taking a bath, you need to keep your body dry to avoid catching a cold.

4. Study hard, and you will get high scores. (No error)
5. Practice ping-pong hard, or you will lose the game. (No error)

6. Work hard, and you will earn more money. (No error)
7. Work hard, or you will become poor. (No error)

8. Exercise hard, and you will become an excellent bodybuilder in the future. (No error)
9. Exercise hard, or you will become sick.