The head inflated with air surfaces a smooth yet firm coolness, verifying its utmost flexibility, to perhaps over insinuate the youth of this character.

头部膨涨充气使作品具有流畅且坚实的冷酷外表，验证它最大限度的柔韧性，也许藉此深化年轻的特质。

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Researchers also found that balls inflated at higher pressure hit the head with greater acceleration, even when kicked at the same speed.

WSJ: Soccer 'Header' Impact Likened to Hard Punch