6 letter words:
snifts9,
5 letter words:
fists8,
sifts8,
snift8,
snits5,
4 letter words:
fins7,
fist7,
fits7,
sift7,
nits4,
sins4,
sist4,
sits4,
snit4,
tins4,
3 letter words:
fin6,
fit6,
ifs6,
sif6,
ins3,
its3,
nis3,
nit3,
sin3,
sis3,
sit3,
tin3,
tis3,
2 letter words:
if5,
in2,
is2,
it2,
si2,
st2,
ti2,
