| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | that must have [be] [prep] | 6 |
|
| 2 | that must have been [prep] | 6 |
|
| 3 | that must have [be] [prep] | 6 |
|
| 4 | that must have be [prep] | 6 |
|
| 5 | that must have [been] [prep] | 6 |
|
