He sat a short distance from them, his eyes on Jon.
( He ( ( ( ( sat ( a ( short distance ) ) ) ( from ( ( them , ) ( his eyes ) ) ) ) ( on Jon ) ) . ) )
(ROOT (S (NP (PRP He)) (VP (VBD sat) (NP (DT a) (JJ short) (NN distance)) (PP (IN from) (NP (NP (PRP them)) (, ,) (NP (PRP$ his) (NNS eyes)))) (PP (IN on) (NP (NNP Jon)))) (. .)))
Looking at Jon, he sat a short distance from them.
( ( Looking ( at Jon ) ) ( , ( he ( ( ( sat ( a ( short distance ) ) ) ( from them ) ) . ) ) ) )
(ROOT (S (S (VP (VBG Looking) (PP (IN at) (NP (NNP Jon))))) (, ,) (NP (PRP he)) (VP (VBD sat) (NP (DT a) (JJ short) (NN distance)) (PP (IN from) (NP (PRP them)))) (. .)))