| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must [adv] have [been] [adv] | 16 |
|
| 2 | must [adv] have been [adv] | 16 |
|
| 3 | must [adv] have [been] [adv] | 16 |
|
| 4 | must [adv] have [been] [adv] | 15 |
|
