心室肌细胞3期复极化是 外流形成的
A．Na+
B．K+
C．Ca2+
D．C1-
E．Mg2+
参考答案：B
During the day, we’ll walk across the land, ____ the footprints of big animals.
A．will follow
B．follow
C．following
D．to follow
—Excuse me, do you know ________________?
—Oh, no! Nothing is wrong with her.
A．what’s wrong with her
B．what wrong is with her
C．what is the matter to her
D．what the matter is to her
