嗜睡
参考答案:
是一种病理性倦睡,可被唤醒,一旦刺激移去,又迅速入睡,是意识障碍早期表现。
Look at the bridge! It _____ ten years ago. [ ]
A. built
B. had built
C. was built
D. was building
下列说法中正确的是( )
A.原命题是真命题,则它的逆命题不一定是真命题
B.原命题是真命题,则它的逆命题不是命题
C.每个定理都有逆定理
D.只有真命题才有逆命题