The spelling of the word "more slumbery" can be explained using the International Phonetic Alphabet (IPA). The first syllable "mor" is pronounced as /mɔːr/ with a long o sound. The second syllable "e" is pronounced as /iː/ with a long e sound. The third syllable "slum" is pronounced as /slʌm/ with a short u sound. The fourth syllable "ber" is pronounced as /bər/ with a schwa sound. The final syllable "y" is pronounced as /i/ with a short i sound. Taken together, "more slumbery" is pronounced as /mɔːr iː slʌm bər i/.