( Saturn ( ( has ( been ( ( ( visited ( in ( flybys ( in ( the 1970s ) ) ) ) ) ( ( ( by ( ( ( ( NASA 's ) ( Pioneer 10 ) ) and ) 11 ) ) and ) ( in 1980-81 ) ) ) ( by ( the ( Voyager ( 1 ( and ( 2 spacecraft ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Saturn)) (VP (VBZ has) (VP (VBN been) (VP (VBN visited) (PP (IN in) (NP (NP (NNS flybys)) (PP (IN in) (NP (DT the) (NNS 1970s))))) (PP (PP (IN by) (NP (NP (NP (NNP NASA) (POS 's)) (NNP Pioneer) (CD 10)) (CC and) (NP (CD 11)))) (CC and) (PP (IN in) (NP (CD 1980-81)))) (PP (IN by) (NP (DT the) (NNP Voyager) (CD 1) (CC and) (CD 2) (NN spacecraft)))))) (. .)))
Saturn has been visited in flybys in the 1970s by NASA's Pioneer 10 and 11 and in 1980-81 by the Voyager 1 and 2 spacecraft.
(ROOT (S (NP (DT The) (NN voyager) (CD 1) (NN spacecraft)) (VP (VBD visited) (NP (NN saturn)) (PP (IN in) (NP (CD 1980)))) (. .)))