This image was donated by Pearson Scott Foresman, an educational publisher, to Wikimedia Commons, and is thereby in the Public Domain 生物学 black_and_white 植物学 亚麻 1
A cartoon picture of cotton (or wool) being stretched and spun to make thread 棉花 羊毛 亚麻 Spinning cotton into thread
This image was donated by Pearson Scott Foresman, an educational publisher, to Wikimedia Commons, and is thereby in the Public Domain 生物学 black_and_white 植物学 亚麻 2