Final answer:
In Spanish, "ciento" changes to "cien" before masculine nouns, the number "mil" (thousand), and the word "milliones" (millions).
Step-by-step explanation:
In Spanish, the word "ciento" changes depending on the noun or the numbers "mil" and "milliones". Before masculine nouns, "ciento" becomes "cien". For example, "cien dólares" (a hundred dollars). Before feminine nouns, it becomes "ciento". For example, "ciento cincuenta páginas" (one hundred and fifty pages).
Before the number "mil" (thousand) and the word "milliones" (millions), "ciento" becomes "cien". For example, "cien mil personas" (a hundred thousand people) and "cien millones de dólares" (a hundred million dollars).
However, when "ciento" precedes the word for thousand ("mil") and the word for millions ("millones"), it changes its form. Instead of "ciento," you would use "cien" before "mil" and "millones", making it "cien mil" (one hundred thousand) and "cien millones" (one hundred million)