The spelling of "hast sized up" can be understood by breaking it down into its phonetic components. "Hast" is pronounced as /hæst/, with the 'a' sound as in "cat" and the 's' sound at the end. "Sized" is pronounced as /saɪzd/, with the 'i' sound as in "eye" and the 'z' sound at the end. "Up" is pronounced as /ʌp/, with the 'u' sound as in "cup" and the 'p' sound at the end. Altogether, the word is pronounced as /hæst saɪzd ʌp/.