( ( ( Look ( at ( slide ( under microscope ) ) ) ) ( to ( observe ( skin cells ) ) ) ) . )
(ROOT (S (VP (VB Look) (PP (IN at) (NP (NP (NN slide)) (PP (IN under) (NP (NN microscope))))) (S (VP (TO to) (VP (VB observe) (NP (NN skin) (NNS cells)))))) (. .)))
Look at slide under microscope to observe skin cells.
(ROOT (S (NP (DT A) (NN microscope)) (VP (MD would) (ADVP (RBS best)) (VP (VB help) (S (NP (DT a) (NN person)) (VP (VB observe) (NP (NP (DT the) (NNS parts)) (PP (IN of) (NP (DT a) (NN plant) (NN cell)))))))) (. .)))