( Autotrophs ( also ( ( are ( referred ( to ( as ( primary producers ) ) ) ) ) . ) ) )
(ROOT (S (NP (NNS Autotrophs)) (ADVP (RB also)) (VP (VBP are) (VP (VBN referred) (PP (TO to) (NP (RB as) (JJ primary) (NNS producers))))) (. .)))
Autotrophs also are referred to as primary producers.
(ROOT (S (NP (NNS Autotrophs)) (VP (VBZ is) (NP (NP (DT another) (NN name)) (PP (IN for) (NP (NNS producers))))) (. .)))