( ( ( ( ( ( Make sure ) ( ( the tractor ) ( is level ) ) ) and ) not ) ( tilted ( to ( the ( slope angle ) ) ) ) ) . )
(ROOT (S (S (S (VP (VB Make) (ADJP (JJ sure)))) (NP (DT the) (NN tractor)) (VP (VBZ is) (NP (NN level)))) (CC and) (RB not) (S (VP (VBN tilted) (PP (TO to) (NP (DT the) (NN slope) (NN angle))))) (. .)))
Make sure the tractor is level and not tilted to the slope angle.
(ROOT (S (NP (NP (NNP Instruments)) (SBAR (WHNP (WDT that)) (S (VP (VB measure) (NP (NP (DT the) (NN angle)) (PP (IN of) (NP (NP (DT the) (NN slope)) (PP (IN of) (NP (DT a) (NN volcano)))))))))) (VP (VBP are) (VP (VBN called) (NP (NN tilt) (NNS meters)))) (. .)))