Comparison may make something appear more beautiful than it is when ______ alone.

A．to see

B．seeing

C．is seen

D．seen

镇肝息风汤中重用生怀牛膝的主要用意是（）

A.补益肝肾，祛瘀通经

B.补益肝肾，引血下行

C.补益肝肾，导热下行

D.活血祛瘀，利水通淋

E.祛瘀通脉，引血下行