Answer:
Explanation:
Tough question.
Spiritual.
Love (if ever there was a misused word, it is love). I used to ask my classes what this sentence means "I love hunting." Try that one on. I don't know if you are dating someone, but how can you say "I love you." and "I love hunting." and not have something terribly wrong with the definition of the verb. One implies treasuring someone. The other means outfoxing a fox and murder.
Religion. Why are there so many different ones? The claim that there is only one true one makes the definition elusive to say the least. And it has caused a great deal of trouble.
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Geometry: You have to know what a line segment is before you can say that one segment bears a relationship to another one.
You have to be able to define a point before you can calculate an intersection point of 2 lines or 2 curves or more.
You have to be able to define almost any term in geometry so that you can restrict enough to make it useful.