下列哪项不是影响冠脉循环的主要因素（）

A.平均动脉压

B.主动脉舒张压

C.平均肺动脉压

D.回心血量

E.主动脉收缩压

Chinese _____ by more and more people in the world. So we must learn it well.[ ]

A. speaks

B. spoke

C. is spoken

D. will speak