* * 清洁度检查结果为Ⅰ度时，其中的上皮细胞数应在（）
A.-
B.+
C.++
D.+++
E.++++
参考答案：E
—What's the time, please?
—______ seven thirty. [ ]
A. That's
B. Is
C. It's
D. This's
