<|im_start|>user
Given this paragraph about the description of wakesurfing, what is needed to generate the wave?

Context:
Wakesurfing is a water sport in which a rider trails behind a boat, riding the boat's wake without being directly pulled by the boat. After getting up on the wake, typically by use of a tow rope, the wakesurfers will drop the rope, and ride the steep face below the wave's peak in a fashion reminiscent of surfing. Wakesurfers generally use special boards, designed specifically for wakes.<|im_end|>
<|im_start|>assistant
a boat<|im_end|>
