(S (S (S (BASENP (JJ Iranian) (JJ naval) (NNS forces)) (VP (VP (VBD detained) (BASENP (DT the) (NNPS Britons))) (PP (IN on) (NP (BASENP (DT the) (JJ 25th)) (PP (IN of) (BASENP (NNP November))))))) (SBAR (IN as) (S (BASENP (PRP they)) (VP (VP (VP (VBD sailed) (PP (IN from) (BASENP (NNP Bahrain)))) (PP (TO to) (BASENP (NNP Dubai)))) (PP (IN for) (BASENP (DT a) (NN race))))))) (PERIOD .))