第一节 单词拼写（共10小题；每小题1分，满分10分）
75. The plane is flying at an a________ of 10,000 feet.
76. He is so s________ that no one can persuade him to do anything.
77. Although they are twins, they look ___________ (完全地) different.
78. I didn’t do it on p__________ --- It was an accident.
