下列词语描述气候的是[ ]
A、风和日丽
B、四季如春
C、暴风骤雨
D、阴转多云
答案：B
What impressed me most in his report lies in the words to bring about an _________ of the conditions of the working men and women．
A．improvement
B．advance
C．increase
D．achievement
《地表水环境质量标准》（GB3838－2002）中，集中式生活饮用水中硫酸盐以SO42-计）的标准限值是（）mg/L.
A.250
B.300
C.100
