( Galileo ( ( is ( thought ( to ( have ( been ( the ( first ( astronomer ( to ( ( ( build and ) use ) ( a telescope ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Galileo)) (VP (VBZ is) (VP (VBN thought) (S (VP (TO to) (VP (VB have) (VP (VBN been) (NP (DT the) (JJ first) (NN astronomer) (S (VP (TO to) (VP (VB build) (CC and) (VB use) (NP (DT a) (NN telescope)))))))))))) (. .)))
Galileo is thought to have been the first astronomer to build and use a telescope.
(ROOT (S (NP (NNP Galileo)) (VP (VBD built) (NP (DT the) (JJ first) (NN telescope))) (. .)))