The spelling of the word "haddest one number" can be confusing, but it follows the English grammar rules of the past tense verb "to have". "Haddest" is a contraction of "had" and "est", meaning you had something in the past. "One" is simply the number 1, while "number" is spelled phonetically as "nʌmbər". So altogether, "haddest one number" means "you had one number". Understanding English pronunciation and spelling can be tricky, but with practice and phonetic transcription, it can become easier.