You should roll the wool into a ball before you start knitting.

在你开始编织之前，你应该把毛线卷成一个球。

youdao

He wound the wool into a ball.

他把毛线缠绕成一团。

《牛津词典》

See how your cat has messed up my ball of wool.

瞧你的猫把我的绒线球弄乱了。

youdao

Knit-Chicks meet regularly at various London venues and say anyone with a ball of wool is welcome to join.

BBC: NEWS | UK | England | London | Chicks knit at first flick meet

Aluminum foil as glassware scrubber: To get baked-on food off a glass pan or an oven rack, use dishwashing liquid and a ball of foil in place of a steel-wool soap pad, says Mary Findley, president of the cleaning-products developer Mary Moppins.

CNN: New uses for Thanksgiving items