一均质等截面直杆的重心在其全长的中点处,若把它完成半圆形,其重心在圆心处。()
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The girl makes a magic word to save Wilbur from being slaughtered.()
There is a mother pig in the barn, who is kind to Wilbur.()
Belle's favorite book is about far-off places, daring sword fights, magic spells, a prince in disguise.()
There is a monster living in the old man's house in the movie “Monster House”.()