They're actually both teachers.
( They ( ( ( 're actually ) ( both teachers ) ) . ) )
(ROOT (S (NP (PRP They)) (VP (VBP 're) (ADVP (RB actually)) (NP (DT both) (NNS teachers))) (. .)))
They are both pilots.
( They ( ( are ( both pilots ) ) . ) )
(ROOT (S (NP (PRP They)) (VP (VBP are) (NP (DT both) (NNS pilots))) (. .)))