在气相色谱中，分离度R总是越大越好，相邻两组分分离的会越好（）.
参考答案：错
It was in the hall______ we usually have dinner______ we had a dancing party last night. [ ]
A. where; that
B. that; where
C. where; which
D. which; where
通货紧缩的基本标志是（）。
A.国民收入持续下降
B.物价总水平持续下降
C.货币供应量持续下降
D.经济增长率持续下降
