This is the 13690th most frequent Russian word.
неосторожных
"Неосторожных" means "careless" or "of the careless" in English.
In this sentence, 'неосторожных' is used as an adjective describing 'пешеходов', emphasizing their lack of caution.
Неосторожных пешеходов часто можно встретить на оживленных улицах.
Careless pedestrians are often encountered on busy streets.
Here, 'неосторожных' is a descriptive adjective modifying 'действий', highlighting the risky nature of the actions.
Никто не осудит вполне естественного страха перед неосторожных действий.
No one will blame the quite natural fear of reckless actions.
In this example, 'неосторожных' qualifies 'занятий', pointing out the carelessness associated with the activities.