1. Q: What’s the problem here?
A: A light bulb is burned out.
2. Q: What do I have to do?
A: You have to change it.
or
A: You have to take out the old light bulb and put in a new one.
3. Q: How is a light bulb removed?
A: The light bulb is unscrewed and taken out of the socket.
4. Q: How is a new light bulb put in?
A: A new light bulb is screwed into the socket.
5. Q: How many people does it take to change a light bulb?
A: It just takes one person to do this.
(This is kind of a joke that you often hear in the United States: How many ____________s does it take to change a light bulb? In the empty space you put a type of person–a lawyer, a doctor, an English teacher, etc.)
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