房水具有营养以下组织的功能（）
A.结膜
B.视网膜
C.角膜
D.玻璃体
E.晶状体
参考答案：C, D, E
仓储按建筑形态可分为（）。
A.平房型仓储
B.配送中心型仓储
C.地下仓储或洞库型仓储
D.高货架立体仓储
Only when he arrived home _____ that he had left his key in the office.
A．will he realize
B．he did realize
C．did he realize
D．should he realize
