1. I am good at mimicking others. I want to mimick President No Muhyeon for the elderly people.

2. I am good at walking on my hands. I want to walk on my hands to surprise the elderly people.

3. I am good at doing hard work. I want to carry heavy things for the club members and the elderly people.

4. I am good at doing taekwondo.I want to do taekwondo to please the elderly people.

5. I am good at doing voices. I want to do my teacher's voices for the elderly people.

6. I am good at cutting hair. I want to cut hair for the elderly people.

7. I am good at a knee-wrestling match. I want to have a knee-wrestling match for the elderly people.

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Would you check the sentences? Correct errors, please. Thank you.

Only a few corrections:

1. mimic (but you're right to keep the k in mimicking)

4. I am good at taikwondo. I want to demonstrate taikwondo ...

5. ... my teachers' voices ...

Everything else seems fine.

1. I am good at mimicking others. I want to mimic President Moon Jae-in for the elderly people.

Explanation: To correct the name of the President, change "No Muhyeon" to "Moon Jae-in."

2. I am good at walking on my hands. I want to walk on my hands to surprise the elderly people.

3. I am good at doing hard work. I want to carry heavy things for the club members and the elderly people.

4. I am good at doing taekwondo. I want to perform taekwondo to please the elderly people.

5. I am good at doing voices. I want to imitate my teachers' voices for the elderly people.

Explanation: Instead of "do my teacher's voices," use "imitate my teachers' voices" to express the intention more clearly.

6. I am good at cutting hair. I want to offer haircuts to the elderly people.

Explanation: The phrase "cut hair for the elderly people" can be changed to "offer haircuts to the elderly people" to make it more natural.

7. I am good at a knee-wrestling match. I want to have a knee-wrestling match with the elderly people.

Explanation: To indicate that the knee-wrestling match will be between the speaker and the elderly people, change "for" to "with" in the sentence.