| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [pers pn] must have [been] [v-ing] [prep] | 56 |
|
| 2 | [pers pn] must have [been] [v-ing] [prep] | 56 |
|
| 3 | [pers pn] [modal v] have [been] [v-ing] for | 38 |
|
| 4 | [pers pn] must have [been] [verb] for | 18 |
|
| 5 | [pron] must have [been] [v-ing] for | 15 |
|
| 6 | [pers pn] must have [been] [v-ing] for | 15 |
|
| 7 | [pers pn] must [verb] [been] [v-ing] for | 15 |
|
| 8 | [pers pn] must have [be] [v-ing] for | 15 |
|
