普通砼浇水自然养护时间不得少于（）
A.2d
B.7d
C.14d
D.28d
参考答案：B
Relax! ______ you finish this English exam, you'll be free and feel on the top of the world.
You can make it if you put your heart into it! [ ]
A．As well as
B．As soon as
C．As good as
何谓蛛网膜下腔?蛛网膜下腔穿刺需经哪些层次？
