| Subclasses of obligatory danshu | Syntactic patterns | Specific expressions | No. of instances | Percent (%) |
| Positive obligations | 1. danshi, yingdang... | 1) danshi, yingdang... | 44 | 27.5% |
| 2) dan yingdang... | 13 | 8.13% | ||
| 3) yingdang... | 3 | 1.88% | ||
| 2. danshi, bixu... | 1) danshi, bixu... | 6 | 3.75% | |
| 2) dan bixu... | 3 | 1.88% | ||
| 3) danshi bixu... | 2 | 1.25% | ||
| 3. Other syntactic patterns | 1) danshi, ... you... | 6 | 3.75% | |
| 2) danshi, ... bu yingxiang... | 2 | 1.25% | ||
| 3) danshi ... de, ... geiyu... | 1 | 0.63% | ||
| 4) danshi ... de, ... yi... | 1 | 0.63% | ||
| 5) danshi ... de, ... shiyong... | 1 | 0.63% | ||
| Negative obligations | 1. danshi, bude... | 1) danshi, bude... | 40 | 25% |
| 2) dan bude... | 21 | 13.13% |