7 letter words
PENGUIN​10
6 letter words
PENING​9
GUINEP​9
INGENU​7
5 letter words (6 words)
ENNUI​5
PENNI​7
GENIP​8
UNPEG​8
UNPEN​7
UNPIN​7
4 letter words (9 words)
NINE​4
PINE​6
PING​7
GINN​5
GIEN​5
PENI​6
PUNG​7
PEIN​6
GENU​5
3 letter words (26 words)
INN​3
PIN​5
GNU​4
GUN​4
ING​4
PEN​5
ENG​4
GEN​4
PIE​5
PIG​6
UNI​3
PEG​6
NIP​5
GIN​4
NIE​3
NEG​4
PUG​6
NUN​3
PUN​5
NEP​5
2 letter words (11 words)
IN​2
UP​4
EN​2
UN​2
NE​2
GI​3
PI​4
PE​4
NU​2
UG​3
GU​3