using Nikse.SubtitleEdit.Core; // Load subtitle file Subtitle subtitle = new Subtitle(); subtitle.Load(@"C:\mySubtitleFile.srt"); // Shift all subtitles down by one subtitle.Renumber(2); // Save the modified subtitle file subtitle.Save(@"C:\myModifiedSubtitleFile.srt");In this example, the Renumber method is called with a parameter of 2, which means all subtitles starting from index 2 will be shifted down by one. Overall, Nikse.SubtitleEdit.Core is a useful package library for working with subtitle files in C#.