impregnable Non-English speakers have been known to think this means inconceivable.
( ( impregnable ( Non-English speakers ) ) ( ( have ( been ( known ( to ( think ( ( this means ) inconceivable ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJ impregnable) (JJ Non-English) (NNS speakers)) (VP (VBP have) (VP (VBN been) (VP (VBN known) (S (VP (TO to) (VP (VB think) (S (NP (DT this) (NNS means)) (ADJP (JJ inconceivable))))))))) (. .)))
All non-English speakers understand its meaning.
( ( All ( non-English speakers ) ) ( ( understand ( its meaning ) ) . ) )
(ROOT (S (NP (DT All) (JJ non-English) (NNS speakers)) (VP (VBP understand) (NP (PRP$ its) (NN meaning))) (. .)))