先通读下列短文，掌握其大意，然后根据短文内容和所给首字母，在空格内填入一个适当的词，使短文意思完整。所填单词在题后横线上必须完整写出

A young man saw an elderly couple (夫妇) sitting down to lunch at McDonald’s. They had o_____小题1: one meal and an extra drink cup. The gentleman c_______小题2:divided the hamburger in half and then counted out the fries, one for him, one for her, u_________小题3: each had half of them.

Then he p_______小题4:half of the soft drink into the extra cup and put that in front of his wife. The old man then began to eat and his wife sat w________小题5:, with her hands folded (交叉) in her lap.

The young man decided to ask w_________小题6: they would allow him to buy a________ 小题7: meal for them. The old gentleman said, “Oh, no, we have b______ 小题8: married for 50 years, and everything has always been and will a______小题9:be shared, 50/50.” The young man then asked the wife if she was going to eat, and she replied, “It’s his t_______小题10:to eat with the teeth.”

正常二尖瓣血流及成人平均流速为（）

A.射流，平均流速为1.5m／s

B.湍流，平均流速为0.9m／s

C.层流，平均流速为1.5m／s

D.层流，平均流速为0.9m／s

E.涡流，平均流速为1.3m／s