(S (S (ADVP (RB However)) (COMMA ,) (S (S (NP (BASENP (JJ additional) (NNS problems)) (PP (IN with) (BASENP (DT a) (JJ rotary) (NN joint)))) (VP (VP (VBD were) (RB not)) (VP (VBN repaired)))) (CC and) (S (SBAR (IN if) (S (BASENP (PRP they)) (VP (VP (VBP are) (RB not)) (VP (VBN repaired))))) (S (BASENP (PRP they)) (VP (MD could) (VP (VB interfere) (PP (IN with) (BASENP (JJ further) (NN station) (NN construction))))))))) (PERIOD .))