您要查找的是不是：
- L245A级钢管 L245A-pipe
- X65级钢管 X65 grade steel pipe
- X80级钢管 X80 grade steel pipe
- JP级钢管磷化的研究 PHOSPHATIZATION OF JP GRADE STEEL TUBE
- 钢管 steel tube
- 级联 connection
- 大学英语四级 College English Band 4
- 船级 ship' classification
- 镀锌钢管 galvanized steel tube
- 三级片 third-grade film
- 无级 stepless
- 焊接钢管 welded steel pipe
- 级配 graduation
- 他将望远镜收进一根钢管内。 He slipped the telescope into a steel tube.
- 第二级 secondary
- 大学英语六级考试 CET-6 [College English Test, Band Six]
- 钢管里塞满了脏物。 The steel tubes were clogged with dirty matters.
- 第一级 first step
- 钢管桩 steel pipe pile
- 工业级 technical grade
