单项选择题
A special daymark is a（）.
A.red-and-white octagon B.daymark with a yellow stripe on it C.green square D.yellow diamond
单项选择题 A spanner is a （）.
单项选择题 A slow，gradual fall of the barometer indicates approaching（）.
单项选择题 A slow rise in the barometric pressure forecasts（）.
