A:持续上升
B:持续下降
C:变动不大
D:可能上升,也可能下降
明末科学家徐光启的《天工开物》被译成多种文字,外国学者称它为“中国17世纪的工艺百科全书”。
—Never mind. I _______________ here for only a few minutes.
--- I've spent the whole afternoon reading books.
--- I think you'd better go out and get some _______ air.