 |
| |||
| 环形铁芯 | |||
| 螺旋状岩芯 | |||
| spiral core: 5 phrases in 3 subjects |
| Metallurgy | 3 |
| Technology | 1 |
| Textile industry | 1 |
The server is undergoing maintenance and the site is working in read-only mode. Please check back later.">Add | The server is undergoing maintenance and the site is working in read-only mode. Please check back later.">Report an error
| Get short URL | Language Selection Tips