woolen yarn造句怎么写

Several types of spinning systems have been used in making woolen yarns, for example mule spinning, ring- frame spinning, etc.

Firm - textured, compactly twisted woolen yarn made from long - staple fibers.

To make woolen yarns the fibers are fed to the carding machine where the fiber assemblage is opened or separated, tangles are removed. Fibers are straightened to some degree and impurities are removed.