Welcome to the English debate. I'd like all of you to take part in this debate. The MC will preside over the debate.

I'd like you, the speakers, to come to the front with desks and chairs and be seated on your chairs facing your classmates.
On the right, three desks and chairs should be placed in a row.
On the left, three chairs and desks should be put in a row.the affirmative team should be seated on the left,and the negative team should be seated on the right.
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Would you check the passage? Correct any errors, please. Thank you. Do you have some more common expressions?

You have the word "debate" three times in the first three sentences. You should delete "over the debate."

Space and capital T is needed in the last section. See it? Also there needs to be a space after the comma in that same sentence. (I know the spaces, capitals and punctuation won't be heard by your audience, but still ... !)

In addition to affirmative and negative, you can also use pros and cons.

Welcome to the English debate. I'd like all of you to take part in this debate. The MC will preside.

I'd like you, the speakers, to come to the front with desks and chairs and be seated on your chairs facing your classmates.
On the right, three desks and chairs should be placed in a row.
On the left, three chairs and desks should be put in a row. The affirmative team should be seated on the left,and the negative team should be seated on the right.
(The pros team should be seated on the left,and the cons team should be seated on the right.)

- Thank you for your help. This is the corrected one.-

The only other thing I'd do, to remove repetition, is to omit these words: "on your chairs" (because you know they won't sit on their desks!!).

Otherwise, it all reads really well!

Welcome to the English debate. I'd like all of you to participate in this debate. The MC will be presiding over the debate.

I would like the speakers to come to the front with desks and chairs and be seated facing their classmates.

On the right, three desks and chairs should be placed in a row.

On the left, three chairs and desks should be put in a row. The affirmative team should be seated on the left, and the negative team should be seated on the right.

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Regarding your question about common expressions, here are a few more:

1. "It's a piece of cake" - This means something is very easy to do.
Example: "Don't worry, finishing this task will be a piece of cake."

2. "Break a leg" - This is a way to wish someone good luck, especially before a performance or important event.
Example: "You're going to do great in your presentation. Break a leg!"

3. "Bite the bullet" - This phrase means to face a difficult situation with bravery and determination.
Example: "I know it's hard, but you have to bite the bullet and confront him about the issue."

4. "Hit the nail on the head" - This expression means to accurately identify or describe something.
Example: "John's analysis of the problem hit the nail on the head. He knew exactly what was causing the issue."

5. "Cost an arm and a leg" - This phrase is used to describe something that is very expensive.
Example: "I would love to go on that vacation, but it would cost an arm and a leg."

I hope these expressions are helpful. If you have any more specific questions, feel free to ask!