Mrs. Green was the manager of a large company and she frequently had to have meetings with other business people in a room in her building. She did not smoke at all, but many of the other people at the meetings did, so she often found the air during the meetings terrible.

　　One day,after an hour, her throat and eyes were sore and she was coughing a lot, so she called a big air conditioning company and asked them to work out how much it would cost to keep the air of the meeting room in her building really clean.

　　After a few days the air conditioning company sent in two estimates2 for Mrs. Green to choose from. One estimate1 was for $5,000 to put in new air conditioning, and the other was for $5.00 for a sign which said, NO SMOKING.

　　格林太太是一家大公司的經(jīng)理，必須經(jīng)常在她大廈內(nèi)的房間跟其他的生意人開會。 她本人不抽煙，但是許多其他來開會的人卻抽煙，所以她常常覺得會場里的空氣令人難受。

　　有一天，開了一小時的會，她喉嚨和眼晴都很痛，而且咳口嗽得很厲害，所以她就請了一家處理空氣調(diào)節(jié)的大公司，請他們計算一下要花多少錢，才能使大廈會議室內(nèi)的空氣保持絕對干凈。

　　幾天后受理空氣調(diào)節(jié)的公司開了兩張估價單供格林太太選擇。 一張是花五千元來安置新的空氣調(diào)節(jié)設備，另一張是花五塊錢買一個“請勿抽煙”的牌子。