题目

（每空1分，共12分）大多数鸟都适于飞行，家鸽是空中飞行动物的代表，它有很多适于飞行生活的形态结构和生理特点，请你回忆并回答：(1)从外形来看：体呈_______型，可减小空气的阻力。前肢变为_______。(2)从骨骼来看：骨很薄，长骨_______。(3)从肌肉来看： _______发达，能牵动两翼完成飞行动作。(4)从消化看：食量大，消化能力强，提供_____     __，以供飞行之用，直肠_______，粪便及时排出体外。(5)从呼吸来看：有        辅助呼吸，提高了气Pip ______ a gentleman and ______ Estella’s love, who is a beautiful girl. A. is bent to becoming; winning                 B. is bent on becoming; win C. is determined to become; winning              D. is determined to become; win