直线比例尺千米用数字表示是_______。
1：30000000
—Have you met Mr. Li?
—Yes. When I arrived, he for Shanghai to attend a national conference.
A. just left
B. had just left
C. just leaves
D. was just leaving
线路图
千米用数字表示是_______。
千米用数字表示是_______。