The top thread is then pulled up by the take-up arm.
( ( The ( top thread ) ) ( ( ( is then ) ( ( pulled up ) ( by ( the ( take-up arm ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ top) (NN thread)) (VP (VBZ is) (ADVP (RB then)) (VP (VBN pulled) (PRT (RP up)) (PP (IN by) (NP (DT the) (JJ take-up) (NN arm))))) (. .)))
The top thread is pulled by the leg.
( ( The ( top thread ) ) ( ( is ( pulled ( by ( the leg ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ top) (NN thread)) (VP (VBZ is) (VP (VBN pulled) (PP (IN by) (NP (DT the) (NN leg))))) (. .)))