"Hadst relation" is not a commonly used phrase in modern English, but it can be broken down phonetically using IPA transcription. "Hadst" is pronounced "hædst," with a short "a" sound as in "cat" and a "d" sound followed by a "st" cluster. "Relation" is pronounced "rɪˈleɪʃən," with a short "i" sound as in "sit," a flap "r," and a long "a" sound as in "say." Together, the phrase would be pronounced "hædst rɪˈleɪʃən."