This means that after sewing a bundle of items of one color, an operator must not only change the needle thread but also put in a new bobbin for each new color of fabric.
( This ( ( means ( that ( ( after ( sewing ( ( a bundle ) ( of ( items ( of ( one color ) ) ) ) ) ) ) ( , ( ( an operator ) ( ( ( ( ( must not ) only ) ( change ( the ( needle thread ) ) ) ) but ) ( also ( put ( in ( ( a ( new bobbin ) ) ( for ( ( each ( new color ) ) ( of fabric ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT This)) (VP (VBZ means) (SBAR (IN that) (S (PP (IN after) (S (VP (VBG sewing) (NP (NP (DT a) (NN bundle)) (PP (IN of) (NP (NP (NNS items)) (PP (IN of) (NP (CD one) (NN color))))))))) (, ,) (NP (DT an) (NN operator)) (VP (VP (MD must) (RB not) (ADVP (RB only)) (VP (VB change) (NP (DT the) (NN needle) (NN thread)))) (CC but) (VP (ADVP (RB also)) (VBD put) (PP (IN in) (NP (NP (DT a) (JJ new) (NN bobbin)) (PP (IN for) (NP (NP (DT each) (JJ new) (NN color)) (PP (IN of) (NP (NN fabric)))))))))))) (. .)))
Sewing a bundle of items of one color means the bobbin and thread have to be changed.
( ( Sewing ( ( ( a bundle ) ( of ( items ( of ( one color ) ) ) ) ) ( means ( the ( ( bobbin and ) thread ) ) ) ) ) ( ( have ( to ( be changed ) ) ) . ) )
(ROOT (S (NP (NP (NNP Sewing)) (SBAR (S (NP (NP (DT a) (NN bundle)) (PP (IN of) (NP (NP (NNS items)) (PP (IN of) (NP (CD one) (NN color)))))) (VP (VBZ means) (NP (DT the) (NN bobbin) (CC and) (NN thread)))))) (VP (VBP have) (S (VP (TO to) (VP (VB be) (VP (VBN changed)))))) (. .)))