单项选择题 丁二酸俗名是 A. 草酸 B. 酸酐 C. 酯 D. 蚁酸 E. 琥珀酸
单项选择题 While these major players gain the bulk of the attention, they are far from alone.A、There are more people “keeping up with the Joneses” than you think. B、There are people “keeping up with the Joneses” all around the world.
问答题 纬平针织物横向边缘向( )卷边。(工艺正面、工艺反面)。