This is the 355th most frequent Japanese word.
事故
Accident.
In this sentence, '事故' refers specifically to a traffic accident (交通事故). It indicates an unfortunate event that occurred involving vehicles.
彼は昨日の交通事故で怪我をした。
He was injured in yesterday's traffic accident.
Here, '事故' is used in a general sense to denote an undesired event that could happen, emphasizing the need for preventive actions.
この事故を防ぐために、注意を払う必要がある。
It is necessary to pay attention to prevent this accident.
In this instance, '事故' illustrates an unexpected and unintended occurrence (the pen breaking) that happens outside regular expectations, showing its broader use for any mishap.