If you are watching a digital rip of the Blu-ray (such as an MKV or MP4 file) on a computer, you can easily add external English subtitles:
OpenSubtitles: A massive database where you can find multiple versions of English subtitles specifically synced for Blu-ray rips. Subsource: A reliable alternative for TV series subtitles. Game Of Thrones Season 2 Subtitles English Download Bluray
Once you have downloaded your .srt file, you can use a media player like to view them: If you are watching a digital rip of