不属于可摘局部义齿不稳定现象的表现是（）
A.义齿游离端翘起
B.义齿脱落
C.义齿下沉
D.义齿摆动
E.义齿旋转
参考答案：B
影响心输出量的因素有（），（），（）和（）。
It seems water______from this tap for some time. We'll have to take it apart to put it right.
A. had leaked B. is leaking C. leaked D. has been leaking
