单项选择题
In the doldrums you will NOT have（）.
A.high relative humidity B.frequent showers and thunderstorms C.steep pressure gradients D.frequent calms
单项选择题 In the doldrums you can expect（）.
单项选择题 In reading a weather map，closely spaced pressure gradient lines would indicate（）.
单项选择题 In North America the majority of the weather systems move from（）.
