| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be [vb pp] must be | 73 |
|
| 2 | [be] [vb pp] must be | 29 |
|
| 3 | be [vb pp] must be | 29 |
|
| 4 | [is] [vb pp] must be | 24 |
|
| 5 | is [vb pp] must be | 24 |
|
| 6 | are [vb pp] must be | 8 |
|
| 7 | [am/are] [vb pp] must be | 8 |
|
| 8 | [been] [vb pp] must be | 7 |
|
| 9 | been [vb pp] must be | 7 |
|
