at infrequent intervals
at intervals
brokenly
by catches
by fits
by jerks
by skips
by snatches
disconnectedly
discontinuously
exceptionally
exiguously
fitfully
haphazardly
hardly
hardly ever
here and there
in places
in spots
intermittently
irregularly
little
meagerly
not often
now and then
occasionally
on occasion
per saltum
piddlingly
randomly
rarely
scantily
scarcely
scarcely ever
scrimpily
seldom
skimpily
skippingly
sparsely
sparsim
sporadically
spottily
stingily
uncommonly
unfrequently
unoften
frequently
often