1. Let's do some role play with this dialogue. You should take the part of a restaurant owner or a clerk. You should take the part of a customer. Taking turns ordering the food on the menu. Let's go... OK. now change the role/roles. You should start the conversation taking the part of the restaurant owner.

(Would you check the passage? Do we have to use 'role' or 'roles'?)

2. Let's role play with the dialogue.
3. Let's do some role play based on the dialogue.
4. Do the role play with your partner.
5. Do a role play with your friend.
( Are the sentences all correct? Does any need corrections?)

OK. now change the roles.

All of your sentences are correct.

1. The correct sentence would be: "Let's do some role playing with this dialogue. You should take the part of a restaurant owner or a clerk. You should take turns ordering the food on the menu. Let's go... OK, now let's change the roles. You should start the conversation taking the part of the restaurant owner."

2. The sentence "Let's role play with the dialogue" is correct.

3. The sentence "Let's do some role play based on the dialogue" is correct.

4. The sentence "Do the role play with your partner" is correct.

5. The sentence "Do a role play with your friend" is correct.