 |
| |||
| pronumeral; unknown (元，量,物) | |||
| hazard | |||
| number of unknown | |||
| unknown variable | |||
| unknown; unknown number | |||
| indeterminate; unknown quantity | |||
| 未知数: 31 phrases in 13 subjects |
| Air defense | 1 |
| Automobiles | 1 |
| Aviation | 1 |
| Bridge construction | 2 |
| Business | 3 |
| Economy | 1 |
| Explosives and Explosive Ordnance Disposal | 1 |
| Finances | 2 |
| General | 5 |
| Geophysics | 1 |
| Oil / petroleum | 2 |
| Technology | 10 |
| Textile industry | 1 |