jugyouryou no soukishiharai o suru to, gopaasento waribiki ga arimasu.

If you make an early payment of the tuition fee, there is a five percent discount.

Breakdown of jugyouryou no soukishiharai o suru to, gopaasento waribiki ga arimasu.

• を: direct object particle
• が: subject particle
• の: possessive case particle
• と: conditional particle

Questions & Answers about jugyouryou no soukishiharai o suru to, gopaasento waribiki ga arimasu.

What does the particle の do in 授業料の早期支払い?

The の here links two nouns, 授業料 (tuition fee) and 早期支払い (early payment), working like “of” in English. So 授業料の早期支払い literally means “early payment of the tuition fee.”

Why is を used after 早期支払い in 早期支払いをする?

Because 早期支払いをする is a verb phrase meaning “to make an early payment.” The particle を marks 早期支払い as the direct object of the verb する (“to do”).

What kind of conditional is ～をすると, and how does it function here?

This is the と-conditional, which expresses that when the first action happens, the result automatically follows.
• ～をすると = “if/when you do ~, then …”
So 早期支払いをすると、割引があります means “If you make an early payment, there is a discount.”

Why does the sentence use 割引がある instead of 割引になる or 割引される?

• 割引がある literally means “there is a discount,” focusing on the existence/availability of a discount.
• 割引になる would mean “become a discount,” which sounds odd here.
• 割引される (passive “is discounted”) could work in some contexts but changes the nuance to “the price is discounted.”
  In notices or ads, 割引があります is the standard way to say “you get a discount.”