furtively russian
укра́дкой
by stealth, stealthily, furtively
подложи́ть
lay, put, line, add, put some more, put furtively, plant (eg bomb)
подкла́дывать
lay, put, line, add, put some more, put furtively, plant (eg bomb)
подгля́дывать
peep, watch furtively, spy
подгляде́ть
peep, watch furtively, spy