地高辛不宜用于心房颤动。
参考答案：错
. While typing, Helen has a habit of stopping _____ to give her long and flowing hair a smooth.
A．occasionally
B．simultaneously
C．eventually
D．directly
如图某物块沿光滑斜面加速下滑，则关于物块在下滑过程中受力分析正确的（）
A.
B.
C.
D.
