( ( The ( dynamic revetment ) ) ( ( is ( made ( of ( ( small rocks ) ( allowed ( to ( ( move ( under ( wave forces ) ) ) ( to ( an ( equilibrium position ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ dynamic) (NN revetment)) (VP (VBZ is) (VP (VBN made) (PP (IN of) (NP (NP (JJ small) (NNS rocks)) (VP (VBN allowed) (S (VP (TO to) (VP (VB move) (PP (IN under) (NP (NN wave) (NNS forces))) (PP (TO to) (NP (DT an) (NN equilibrium) (NN position))))))))))) (. .)))
The dynamic revetment is made of small rocks allowed to move under wave forces to an equilibrium position.
(ROOT (S (NP (DT A) (VBG moving) (NN car)) (VP (VBZ is) (VP (VBN said) (S (VP (TO to) (VP (VB be) (PP (IN in) (NP (JJ dynamic) (NN equilibrium))) (SBAR (WHADVP (WRB when)) (S (NP (PRP it)) (VP (VBZ is) (NP (CD zero) (JJ net) (NN force)))))))))) (. .)))