| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] what must be [adj] | 8 |
|
| 2 | [prep] [Wh det] must be one | 7 |
|
| 3 | [prep] [Wh det] must be one | 7 |
|
| 4 | [prep] [Wh det] must be [num] | 7 |
|
| 5 | of [Wh det] must be [adj] | 7 |
|
