您要查找的是不是：
- 危险等级标号<各种物质的危险类型和程度的数字分类体系hazard code
- 危险等级danger classes
- 等级grade
- 危险danger
- 确定危险等级assigning degrees of hazard
- 标号grade
- 火灾危险等级fire hazard rating
- 危险的hazardous
- 等级制度hierarchy
- 滑坡危险等级Landslide susceptibility
- 国家计算机等级考试the national computer rank exam
- 有危险be in danger of
- 当今社会弥漫着核战争的危险The threat of nuclear war overhangs modern society.
- 等级观念sense of hierarchy
- 等级考试grade examination
- 攀登陡坡是危险的。It is dangerous to climb up a steep slope.
- 分等级graduation
- 危险信号danger signal
- 电压等级voltage class
- 生命危险life danger
