| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must have been [vb pp] [adv prt] | 41 |
|
| 2 | must have be [vb pp] [adv prt] | 41 |
|
| 3 | must have be [vb pp] out | 11 |
|
| 4 | must have be [vb pp] up | 9 |
|
| 5 | must have be [vb pp] in | 6 |
|
| 6 | must have be [vb pp] down | 5 |
|
