您要查找的是不是：
- DQ级钢DQ class steel
- C级钢low alloy cast steel grade C
- B级钢B grade steel
- E级钢Grade E steel
- X65级钢X65 grade steel
- 钢厂steelworks
- 碳钢carbon steel
- 大学英语四级College English Band 4
- 钢的steel
- 船级ship' classification
- 钢带metal strip
- 三级片third-grade film
- 钢化steel
- 第二级secondary
- 铸钢cast(carbon) steel
- 大学英语六级考试CET-6 [College English Test, Band Six]
- 钢制steeliness
- 第一级first step
- 螺纹钢deformed steel bar
- 工业级technical grade
