( Astronomically ( , ( ( a year ) ( ( is ( ( ( the amount ) ( of time ) ) ( it ( takes ( for ( the ( Earth ( to ( ( make ( one ( complete revolution ) ) ) ( around ( the sun ) ) ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (ADVP (RB Astronomically)) (, ,) (NP (DT a) (NN year)) (VP (VBZ is) (NP (NP (DT the) (NN amount)) (PP (IN of) (NP (NN time))) (SBAR (S (NP (PRP it)) (VP (VBZ takes) (PP (IN for) (NP (DT the) (NN Earth) (S (VP (TO to) (VP (VB make) (NP (CD one) (JJ complete) (NN revolution)) (PP (IN around) (NP (DT the) (NN sun))))))))))))) (. .)))
Astronomically, a year is the amount of time it takes for the Earth to make one complete revolution around the sun.
(ROOT (S (NP (NNP Earth)) (VP (VBZ makes) (NP (DT a) (JJ complete) (NN revolution)) (NP (ADVP (IN around) (NP (DT the) (NN sun)) (PP (IN about) (ADVP (RB once)))) (DT every) (NN year))) (. .)))