( We ( ( can ( ( measure radioactivity ) ( with ( the ( Geiger counter ) ) ) ) ) . ) )
(ROOT (S (NP (PRP We)) (VP (MD can) (VP (VB measure) (NP (NN radioactivity)) (PP (IN with) (NP (DT the) (NNP Geiger) (NN counter))))) (. .)))
We can measure radioactivity with the Geiger counter.
(ROOT (S (NP (NP (DT The) (`` `) (NN counting) ('' ') (NN instrument)) (NP (NN geiger) (NN counter))) (VP (VBZ is) (VP (VBN used) (S (VP (TO to) (VP (VB measure) (NP (NN radioactivity))))))) (. .)))