( ( The gun ) ( ( ( fires electrons ) ( into ( ( different areas ) ( of ( the ( mirror ( to ( make ( ( the surface ) ( ( change ( its shape ) ) ( in ( either ( ( ( a ( more convex ) ) or ) ( concave direction ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN gun)) (VP (VBZ fires) (NP (NNS electrons)) (PP (IN into) (NP (NP (JJ different) (NNS areas)) (PP (IN of) (NP (DT the) (NN mirror) (S (VP (TO to) (VP (VB make) (S (NP (DT the) (NN surface)) (VP (VB change) (NP (PRP$ its) (NN shape)) (PP (IN in) (NP (CC either) (NP (DT a) (JJR more) (NN convex)) (CC or) (NP (JJ concave) (NN direction)))))))))))))) (. .)))
The gun fires electrons into different areas of the mirror to make the surface change its shape in either a more convex or concave direction.
(ROOT (S (NP (DT A) (NN convex) (NN mirror)) (VP (VBZ is) (VP (VBN shaped) (PP (IN like) (NP (NP (DT the) (NN outside)) (PP (IN of) (NP (DT a) (NN bowl))))))) (. .)))
A convex mirror is shaped like the outside of a bowl.