promotor：发起人；倡导者，赞助人

词根词缀：pro-前 + -mot-移动 + -or名词词尾

• substance
• substandard
• substantial
• substantiate
• substantive
• substation
• substitute
• substitution
• substrate
• substratum
• substructure
• subsume
• subtend
• subterfuge
• subterranean
• subtext
• subtility
• subtitle
• subtle
• subtlety
• subtotal
• subtract
• subtraction
• subtropical
• suburb