When you need to apply for extension of SCI journals, please pay attention to the following points:

1. Don't wait until the deadline to apply for an extension. Because most SCI papers are submitted online for revision, if the email applying for extension is submitted too late, it may lead to the deadline set by the system being too late to be revised, and then the revision status of your manuscript will be automatically cleared.

When you apply for an extension, you must clearly tell the editor when you need an extension and the specific reasons.

3. When writing an extension email, you can refer to the following template: "As the deadline approaches, we are urged by the journal. Thank you for giving us the opportunity to overhaul and improve our manuscript to make it suitable for publication in your journal. However, we need an extension period to make further amendments. Can you extend the deadline to XXX? " Or "according to the suggestions and opinions of the reviewers, more experiments need to be added to the manuscript."

4. When applying for extension, make sure that you have completed all the amendments and are ready to submit them before the new deadline. At the same time, possible delay factors should be considered, such as the reaction speed of reviewers and the decision-making of editors.

If the delay is long or there are uncontrollable factors, the editor may suggest that you withdraw the manuscript first. Therefore, when applying for an extension, you must truthfully describe your own situation so that the editor can make the most appropriate decision.