【明報專訊】''Hey, look what I just bought at the flea market!'' Ethro cried, holding high his purchase (購買品). ''That looks like Earth,'' Esper said. ''What did it sell for?'' ''Oh, it sold for very little,'' Ethro said with joy. Sell for refers to the sum of money given to someone to make a purchase (購買). ''It's just another dust collector (閒置品),'' Esper said. ''Maybe, but if I get tired looking at it, I think I can sell it for more than I paid for it,'' Ethro shrugged.