心肌中主要存在的肌酸激酶同工酶是（）
A.CK-MB
B.CK-MM1
C.CK-MM3
D.CK-BB
E.CK-MM2
参考答案：A
It is the first time that I _____ this kind of moon cake. [ ]
A. enjoyed
B. have enjoyed
C. enjoy
D. enjoying
供水管材中非金属管材如何划分的？
