6 letter words:
gutter7,
rutter6,
turret6,
5 letter words:
regur6,
urger6,
truer5,
utter5,
4 letter words:
gert5,
grue5,
tegu5,
trug5,
urge5,
ruer4,
tret4,
true4,
3 letter words:
erg4,
get4,
gue4,
gur4,
gut4,
reg4,
rug4,
teg4,
tug4,
err3,
ret3,
rue3,
rut3,
tet3,
tut3,
ure3,
ute3,
2 letter words:
gu3,
ug3,
er2,
et2,
re2,
te2,
ur2,
ut2,