In autumn leaves ____________ the trees begin to fall. [ ]
A. in
B. at
C. on
答案:C
小麦种子与菜豆种子贮存营养物质的部位分别是( )
A.胚乳和子叶
B.胚芽和子叶
C.胚轴和胚乳
D.胚乳和胚芽
棉制男衬衫