A: There's something wrong with my right hand.
B: What's wrong with it?
A: It aches most of the time.
B: What do you think it is?
A: I don't know. I think it's old age.
B: If it's old age, why don't both of your hands hurt?
A: That's a good question. Maybe it's not old age.
B: Are you right-handed?
A: Yes. All my life.
B: You're wearing out your right hand. Stop using it so much.
A: But I do all my writing with my right hand.
B: Start typing instead. That way your left hand will do half the work.