Let's head off an auxiliary crisis before it happens!
( ( Let 's ) ( ( ( ( head off ) ( an ( auxiliary crisis ) ) ) ( before ( it happens ) ) ) ! ) )
(ROOT (S (NP (NNP Let) (POS 's)) (VP (VBP head) (PRT (RP off)) (NP (DT an) (JJ auxiliary) (NN crisis)) (SBAR (IN before) (S (NP (PRP it)) (VP (VBZ happens))))) (. !)))
If an auxiliary crisis happens, many people will be worried and frightened.
( ( If ( ( an ( auxiliary crisis ) ) happens ) ) ( , ( ( many people ) ( ( will ( be ( ( worried and ) frightened ) ) ) . ) ) ) )
(ROOT (S (SBAR (IN If) (S (NP (DT an) (JJ auxiliary) (NN crisis)) (VP (VBZ happens)))) (, ,) (NP (JJ many) (NNS people)) (VP (MD will) (VP (VB be) (ADJP (JJ worried) (CC and) (JJ frightened)))) (. .)))