mkvmerge -o output.mkv input.mkv --no-audio 2 --language 0:eng subtitles.srt Downloading mkvmerge via MKVToolNix is a fundamental step for anyone serious about managing video files. It is free, cross-platform, and incredibly efficient. Whether you use the intuitive GUI for quick edits or the command line for batch processing, mkvmerge gives you complete, lossless control over your MKV files. Just remember to always download from the official source to keep your system secure. Note: Always ensure you own the legal right to modify any video file before doing so.