摩擦与冲击火花属于（）
A.机械火源
B.化学火源
C.热火源
D.电火源
参考答案：A
— Yao Yuan, a disabled woman, won the National Championships Cup last week.
— My goodness! She ______ a lot of difficulties! [ ]
A. may go through
B. might go through
C. must have gone through
D. ought to have gone through
个 * * 力是一种内在的权力，这种权力取决于( )。
A．领导者自身 B．权力 C．专业技能 D．领导者职位
