7 letter words:
running8,
6 letter words:
urning7,
5 letter words:
ruing6,
unrig6,
inrun5,
inurn5,
4 letter words:
ginn5,
girn5,
grin5,
gurn5,
ring5,
rung5,
ruin4,
3 letter words:
gin4,
gnu4,
gun4,
gur4,
rig4,
rug4,
inn3,
nun3,
nur3,
rin3,
run3,
uni3,
urn3,
2 letter words:
gi3,
gu3,
ug3,
in2,
nu2,
un2,
ur2,