S --> wh C
S --> wh I
S --> aux IP
S --> NP V
S --> NP I
S --> I2
S --> wh
S --> co
IP --> NP I2
C --> aux IP
C --> aux I2
C --> V
C --> NP I
I --> aux I2
I --> aux 
I2 --> NP
I2 --> VI
I2 --> VP
I2 --> AP
I2 --> PP
AP --> adj
V --> v
V --> V NP
VI --> vi
VI --> VI NP
VI --> VI PP
VP --> part
NP --> det N
NP --> N
NP --> pro
NP --> prop
N --> adj N
N --> n
PP -->prep 
PP -->prep NP