leave furtively and stealthily(v)
Synonyms: slip away
sneak away
sneak off
sneak out
steal away
Hypernyms: go away
go forth
leave
Examples: The lecture was boring and many students slipped out when the instructor turned towards the blackboard
pass by(v)
Synonyms: elapse
glide by
go along
go by
lapse
pass
slide by
slip away
slip by
Hyponyms: fell
fly
vanish
Hypernyms: advance
go on
march on
move on
pass on
progress
Examples: three years elapsed