拖鞋的微生物检测项目为（）
A.细菌总数
B.总大肠菌群
C.粪大肠菌群
D.真菌和酵母菌
E.金黄色葡萄球菌
参考答案：D
控制外注式单体液压支柱升柱，承载和降柱的阀组叫（）。
A．安全阀
B．三用阀
C．截止阀
D．控制阀
My parents （）in Hong Kong. They were born there and have never lived anywhere else.
A. live
B. lived
C. were living
D. will live
