( ( One ( way ( that ( ( your eyes ) ( adapt ( to ( the dark ) ) ) ) ) ) ) ( ( is ( that ( ( ( your pupils ) ( -LRB- ( ( ( the ( black dots ) ) ( in ( ( the center ) ( of ( your eyes ) ) ) ) ) -RRB- ) ) ) ( ( dilate ( -LRB- ( ( get bigger ) -RRB- ) ) ) ( to ( let ( in ( more light ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (CD One) (NN way) (SBAR (IN that) (S (NP (PRP$ your) (NNS eyes)) (VP (VBP adapt) (PP (TO to) (NP (DT the) (NN dark))))))) (VP (VBZ is) (SBAR (IN that) (S (NP (NP (PRP$ your) (NNS pupils)) (PRN (-LRB- -LRB-) (NP (NP (DT the) (JJ black) (NN dots)) (PP (IN in) (NP (NP (DT the) (NN center)) (PP (IN of) (NP (PRP$ your) (NNS eyes)))))) (-RRB- -RRB-))) (VP (VBD dilate) (PRN (-LRB- -LRB-) (S (VP (VB get) (ADJP (JJR bigger)))) (-RRB- -RRB-)) (S (VP (TO to) (VP (VB let) (PP (IN in) (NP (JJR more) (NN light)))))))))) (. .)))
One way that your eyes adapt to the dark is that your pupils (the black dots in the center of your eyes) dilate (get bigger) to let in more light.
(ROOT (S (NP (DT The) (NN pupil)) (VP (VBZ is) (NP (NP (DT the) (NN name)) (PP (IN of) (NP (NP (DT the) (JJ black) (NN opening)) (PP (IN in) (NP (NP (DT the) (NN eye)) (SBAR (WHNP (WDT that)) (S (VP (VBZ lets) (SBAR (S (NP (NN light)) (VP (VBP enter))))))))))))) (. .)))