# example grammar

S  -> NP VP

# NPs
NP -> N
NP -> D N
NP -> D A N
NP -> D N PP

# VPs
VP -> V NP
VP -> V
VP -> V NP NP
VP -> V NP PP

# PPs
PP -> P NP

# lexicon
N -> dog
N -> cat
N -> John
N -> Mary
N -> bit
N -> tie
N -> man
N -> woman

D -> a
D -> the

A -> red
A -> big

V -> chases
V -> loves
V -> bit
V -> killed

P -> with
P -> in