After the Soviet Union's twenty-year ban on Vygotsky's writings was lifted in the mid-1950s, his major works reached the West.
( ( After ( ( ( ( the ( Soviet ( Union 's ) ) ) ( twenty-year ban ) ) ( on ( ( Vygotsky 's ) writings ) ) ) ( was ( lifted ( in ( the mid-1950s ) ) ) ) ) ) ( , ( ( his ( major works ) ) ( ( reached ( the West ) ) . ) ) ) )
(ROOT (S (SBAR (IN After) (S (NP (NP (NP (DT the) (NNP Soviet) (NNP Union) (POS 's)) (JJ twenty-year) (NN ban)) (PP (IN on) (NP (NP (NNP Vygotsky) (POS 's)) (NNS writings)))) (VP (VBD was) (VP (VBN lifted) (PP (IN in) (NP (DT the) (JJ mid-1950s))))))) (, ,) (NP (PRP$ his) (JJ major) (NNS works)) (VP (VBD reached) (NP (DT the) (NN West))) (. .)))
The ban remained in place and was never lifted.
( ( The ban ) ( ( ( ( remained ( in place ) ) and ) ( was ( never lifted ) ) ) . ) )
(ROOT (S (NP (DT The) (NN ban)) (VP (VP (VBD remained) (PP (IN in) (NP (NN place)))) (CC and) (VP (VBD was) (VP (ADVP (RB never)) (VBN lifted)))) (. .)))