They were promptly executed.
( They ( ( were ( promptly executed ) ) . ) )
(ROOT (S (NP (PRP They)) (VP (VBD were) (VP (ADVP (RB promptly)) (VBN executed))) (. .)))
They were executed immediately upon capture.
( They ( ( were ( ( executed immediately ) ( upon capture ) ) ) . ) )
(ROOT (S (NP (PRP They)) (VP (VBD were) (VP (VBN executed) (ADVP (RB immediately)) (PP (IN upon) (NP (NN capture))))) (. .)))