( ( In ( ( a ( sample lesson ) ) ( on galaxies ) ) ) ( , ( students ( ( are ( ( introduced ( to ( ( three types ) ( of ( ( galaxies and ) ( our ( Milky ( Way galaxy ) ) ) ) ) ) ) ) ( through ( ( dramatic footage ) ( of ( the ( optical telescopes ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (NP (DT a) (NN sample) (NN lesson)) (PP (IN on) (NP (NNS galaxies))))) (, ,) (NP (NNS students)) (VP (VBP are) (VP (VBN introduced) (PP (TO to) (NP (NP (CD three) (NNS types)) (PP (IN of) (NP (NP (NNS galaxies)) (CC and) (NP (PRP$ our) (NNP Milky) (NNP Way) (NN galaxy)))))) (PP (IN through) (NP (NP (JJ dramatic) (NN footage)) (PP (IN of) (NP (DT the) (JJ optical) (NNS telescopes))))))) (. .)))
In a sample lesson on galaxies, students are introduced to three types of galaxies and our Milky Way galaxy through dramatic footage of the optical telescopes.
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD three) (NNS types)) (PP (IN of) (NP (NNS galaxies))))) (. .)))