The phrase "haddest full plate" is spelled using Middle English orthography. In IPA phonetic transcription, it would be spelled /ˈhædɪst fʊl pleɪt/. The "dd" in "haddest" represents the past tense marker in Middle English, while the "st" indicates the second person singular (you). "Full" is pronounced as "fool" in Middle English, and "plate" is also pronounced differently, with a long "a" sound and a silent "e". Understanding the spelling of Middle English words can help us better understand the evolution of the English language.