то́нко
adverb
thinly; thinly (not thickly)
то́нко очи́ненный каранда́ш
fine pencil-point
то́нко наре́занные ло́мтики хле́ба
in Russian
thinly sliced bread; thin slices of bread
subtly
то́нко разбира́ться
have a subtle / delicate perception
в PREP
of something
delicately, finely (e.g. of produced workmanship)