The accident are mainly caused by violation, misoperation, limit knowledge to the H2S hazards and weaksafety awareness.
事故主要是由于违章及误操作以及对H2S的毒害认识不够、安全意识差引起的。
2
Despite a longstanding commitment to improving road safety, Brazil's numerous initiatives have suffered from weak enforcement.
虽然巴西改善道路安全的承诺由来已久，但其众多行动终因执行乏力而无疾而终。
3
In America, with its weak social safety net and limited student aid, students are far more likely than their counterparts in, say, France to hold part-time jobs while still attending classes.