Q: Can I have a sample mail requesting for more time to submit a revised manuscript?

Firstly, please note that we have edited your question for enhanced clarity.

Ideally, you need to inform the editor of a possible delay, and therefore, the need for more time, soon after you receive the request and timeline for submitting the revised manuscript. You do this by going through the requested changes and estimating how long you will need to complete them. However, it may happen that as you begin working on the changes, you realize you need more time. You can write to the journal asking for an extension, providing a valid reason for this. If the journal thinks the reason is justifiable, they may allow you more time. In case you are not able to submit even then, you will need to submit the revised manuscript as a new submission. You will find templates for requesting more time on revised manuscripts (Chapter 5) and for submitting revised manuscripts as new submissions (Chapter 8), among others, in this handbook (payable): A practical handbook of templates for communicating with the journal

Related questions:

• Can I extend the journal submission deadline for my revised paper?
• Could the paper be rejected if the due date for submitting revisions is over?