( ( ( ( ( ( If ( ( the ( lunar nodes ) ) ( were ( ( stationary ( with respect ) ) ( to ( the stars ) ) ) ) ) ) ( , ( ( each node ) ( would ( be ( ( ( lined up ) ( between ( ( ( the Earth ) and ) ( the Sun ) ) ) ) ( at ( ( the ( same time ) ) ( each year ) ) ) ) ) ) ) ) ) , ) and ) ( eclipses ( would ( occur ( ( ( at ( ( ( the ( same ( two periods ) ) ) ( of time ) ) ( every year ) ) ) , ) ( ( six months ) apart ) ) ) ) ) ) . )
(ROOT (S (S (SBAR (IN If) (S (NP (DT the) (NN lunar) (NNS nodes)) (VP (VBD were) (VP (VBN stationary) (PP (IN with) (NP (NN respect))) (PP (TO to) (NP (DT the) (NNS stars))))))) (, ,) (NP (DT each) (NN node)) (VP (MD would) (VP (VB be) (VP (VBN lined) (PRT (RP up)) (PP (IN between) (NP (NP (DT the) (NN Earth)) (CC and) (NP (DT the) (NNP Sun)))) (PP (IN at) (NP (NP (DT the) (JJ same) (NN time)) (NP (DT each) (NN year)))))))) (, ,) (CC and) (S (NP (NNS eclipses)) (VP (MD would) (VP (VB occur) (PP (IN at) (NP (NP (DT the) (JJ same) (CD two) (NNS periods)) (PP (IN of) (NP (NN time))) (NP (DT every) (NN year))) (, ,) (ADVP (NP (CD six) (NNS months)) (RB apart)))))) (. .)))
If the lunar nodes were stationary with respect to the stars, each node would be lined up between the Earth and the Sun at the same time each year, and eclipses would occur at the same two periods of time every year, six months apart.
(ROOT (S (NP (CD Two)) (VP (VBZ is) (NP (NP (DT the) (JJ minimum) (NN number)) (PP (IN of) (NP (NP (NNS times)) (SBAR (S (NP (DT a) (JJ partial) (NN lunar) (NN eclipse)) (VP (MD will) (VP (VB occur) (NP (DT each) (NN year)))))))))) (. .)))