In fact, a production line is probably never in perfect balance.
( ( In fact ) ( , ( ( a ( production line ) ) ( ( ( ( is probably ) never ) ( in ( perfect balance ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (NN fact))) (, ,) (NP (DT a) (NN production) (NN line)) (VP (VBZ is) (ADVP (RB probably)) (ADVP (RB never)) (PP (IN in) (NP (JJ perfect) (NN balance)))) (. .)))
Most production lines are probably always kept in perfect balance.
( ( Most ( production lines ) ) ( ( ( are probably ) ( always ( kept ( in ( perfect balance ) ) ) ) ) . ) )
(ROOT (S (NP (JJS Most) (NN production) (NNS lines)) (VP (VBP are) (ADVP (RB probably)) (VP (ADVP (RB always)) (VBN kept) (PP (IN in) (NP (JJ perfect) (NN balance))))) (. .)))