This is the 668th most frequent Lithuanian word.
saugiai
"Safely."
In this sentence, 'saugiai' describes the careful manner in which the children act to ensure their security during crossing.
Vaikai saugiai pereina per gatvę.
The children cross the street safely.
Here, 'saugiai' indicates the secure conditions under which the vehicles operate, emphasizing the safety provided by the lighting.
Automobiliai juda saugiai, nes kelias yra gerai apšviestas.
Cars move safely because the road is well lit.
In this usage, 'saugiai' relates to the personal sense of security experienced by the subject, derived from the act of putting on safety equipment.