比较水质浊度分析的方法，能够获得较好线性、灵敏度高、色度影响小的是（）。
A、透射法
B、反射法
C、折射法
D、散射法
参考答案：D
— Has ______ problem been solved?
— Not yet. We're trying to think of ______ way out, but it's quite difficult to find one. [ ]
A. a; the
B. the; a
C. a; a
D. the; the
The young man walked _____ the gate with his uncle. [ ]
A. through
B. over
C. between
D. under
