Judy Vorfeld DID YOU KNOW THAT when using the minus sign, you use a hyphen, not a dash. Word has all kinds of dashes that can pop up when you least expect them: em and em dashes, "named for the length of a typeface's lower-case n and upper-case M respectively," says Wikipedia. Confused? Use the word "minus." To indicate temperatures below zero, write "minus 10" or "5 below zero."