这个短语的字面解释是“买到柠檬”，这是什么意思呢？请看对话：

    A: The used car that I bought is not very good. I think that I bought a lemon.

    B: We often try to save money by buying used cars. Sometimes it doesn’t save us much money but brings a lot of trouble.

    Note: This idiom means to “buy something that is worthless or does not work well,” especially a vehicle. If you bite into a lemon, you make a face on account of the sour taste. If you buy something that doesn’t work out for you, you may also make a sour face. Its first attribution to mean a problematic car was in a Volkswagen advertisement created by Julian Koenig and Helmut Krone as part of an advertisement campaign managed by William Bernbach, all advertising executives with the firm Doyle Dane Bernbach in 1960, which was a follow-up to their Think Small advertising campaign for VW.