蚕丝

jiǎn chá cán sī

检查蚕丝

condition silk

bǎ cán sī zhī chéng xiàn

把蚕丝织成线

spin silk into thread

rén zào sī néng tì dài cán sī ma

人造丝能替代蚕丝吗？

Can rayon substitute for silk?