The spelling of the phrase "be the back of" is straightforward, with each word being pronounced as written. "Be" is pronounced as /bi/, with a short "e" sound. "The" is pronounced as /ði/ or /ðə/, with a voiced "th" sound. "Back" is pronounced as /bæk/, with a short "a" sound and a hard "k" sound. "Of" is pronounced as /əv/ or /ɒv/, with a soft "o" sound. This phrase means to support or stand behind someone or something.