Mary didnt understand such sentences as She is blue today, You are yellow, He has a green thumb(拇指) and He told a white lie. So she went to her teacher for help.

Mary: Mrs Smith, there is a color in each of these sentences. What do they mean?

Mrs Smith: In everyday English, blue sometimes means sad. Yellow sometimes means afraid. A person with a green thumb grows plants well. (善于種植)And a white lie is not a bad one.

Mary: Would you give me an example of a white lie?

Mrs Smith: Certainly. Now I give you a cake. In fact you dont like it, but you wont say it directly. Instead, you say, No, thanks. Im not hungry. Thats a white lie.

Mary: What does He gave me a black look mean?

Mrs Smith: Here black means angry.

Mary: Can you give me an example of green?

Mrs Smith: A green room is a room in which actors or performers rest or wait when they are not performing on stage.

Question:

Everyone wants to visit or live in the White House but not in a green house. You may be a black horse(一鳴驚人的人), but you never want to be a white elephant(累贅). Do you know why?

Key: The White House refers to the official home in Washington D.C. of the President of the USA while a green house is a glass building used for growing plants that need warmth, light and protection, especially in the cold season. A black horse sometimes means someone who is abler or more useful, but a white elephant means a thing that is useless and no longer needed although it may have cost a lot of money.