In 1986, a bomb went off at a disco in Berlin, killing two American soldiers.
( ( In 1986 ) ( , ( ( a bomb ) ( ( ( ( ( ( went off ) ( at ( a disco ) ) ) ( in Berlin ) ) , ) ( killing ( two ( American soldiers ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (CD 1986))) (, ,) (NP (DT a) (NN bomb)) (VP (VBD went) (PRT (RP off)) (PP (IN at) (NP (DT a) (NN disco))) (PP (IN in) (NP (NNP Berlin))) (, ,) (S (VP (VBG killing) (NP (CD two) (JJ American) (NNS soldiers))))) (. .)))
A bomb killed two Americans in Berlin when they were celebrating their birthdays.
( ( A bomb ) ( ( ( ( killed ( two Americans ) ) ( in Berlin ) ) ( when ( they ( were ( celebrating ( their birthdays ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT A) (NN bomb)) (VP (VBD killed) (NP (CD two) (NNS Americans)) (PP (IN in) (NP (NNP Berlin))) (SBAR (WHADVP (WRB when)) (S (NP (PRP they)) (VP (VBD were) (VP (VBG celebrating) (NP (PRP$ their) (NNS birthdays))))))) (. .)))