Answer: Because he didn't see the ewe (U) turn.
The question "Why did the boy sheep plunge off a cliff while chasing the girl sheep?" is a riddle used in math worksheet answered by solving algebra equations.
Try to find the solution for this Why did the boy sheep plunge off a cliff while chasing the girl sheep question.
Also try these Why Riddles:
Why can't a bicycle run faster than a car? Why do witches fly on broomsticks? Why do birds fly South? Why do hens lay eggs?
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