 |
| |||
| 阶段抽样 | |||
|
stage sampling : 60 phrases in 15 subjects |
| Agriculture | 1 |
| Animal husbandry | 1 |
| Biotechnology | 2 |
| Business | 6 |
| Chemistry | 3 |
| Demography | 2 |
| Desert science | 2 |
| Economics | 1 |
| Foreign trade | 1 |
| Genetics | 1 |
| Marketing | 1 |
| Mathematics | 6 |
| Space | 1 |
| Statistics | 20 |
| Technology | 12 |