毛线 

Pinyin: máoxiàn 
Meaning：Yarn  
Sentence：她把山羊毛纺成毛线。 She spins goat's hair into wool/spins wool from goat's hair.

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毛： 

Pinyin: máo 
Meaning: Hair; fur
Radical: 毛
Stokes: 4
Traditional: 毛
Common words/Phrase:
毛衣 [máoyī] 【sweater】
毛巾 [máojīn] 【towel】
毛重 [máozhòng] 【gross weight】
毛孔 [máokǒng] 【pore】
毛坯 [máopī] 【roughcast】

线： 

Pinyin: xiàn
Meaning: Thread; line; string; wire
Radical: 纟
Stokes: 8
Traditional: 綫
Common words/Phrase:
线路 [xiànlù] 【line; circuit】 
线条 [xiàntiáo] 【streak】
线索 [xiànsuǒ] 【clues】
线圈 [xiànquān] 【loop】
线头 [xiàntóu] 【thrum】