Corrected Sentences:
1. Could you please repeat what you just said?
2. Can you provide a detailed explanation?
3. Please refrain from promoting any websites other than EduRev.

Answer:
How to Ask for Repetition:
To request someone to repeat what they just said, use polite language such as "Could you please repeat what you just said?" This way, you are being clear and polite in your communication.

How to Explain in Details:
When providing an explanation, it is important to provide specific details to ensure that the recipient understands the concept. Start by breaking down the topic into smaller parts and explain each part separately. You can also use analogies, examples, and diagrams to make the concept easier to understand.

Promotion of Websites:
Please note that it is not acceptable to promote websites other than EduRev. This is to ensure that the platform remains a safe and trustworthy source of information for all users.

This question falls under the Class 3 category, and hence the response should be provided in less than 300 words. Therefore, it is important to keep the answer concise and to the point, while still providing all the necessary information.

Please repeat again what you said