给出一个英文文本以及一组关键词，要求GPT模型通过自然语言生成问答系统的方式回答有关关键词的问题。
英文文本：“The Mona Lisa is a painting by Leonardo da Vinci. It is one of the most famous paintings in the world.”

关键词：“Mona Lisa”
问答系统：

问：Who painted the Mona Lisa?
答：Leonardo da Vinci painted the Mona Lisa.

问：What is the Mona Lisa?
答：The Mona Lisa is a painting.

问：Is the Mona Lisa a famous painting?
答：Yes, it is one of the most famous paintings in the world.