| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it must [vb infin] be | 782 |
|
| 2 | it must be for | 30 |
|
| 3 | must [vb infin] be for | 14 |
|
| 4 | it must [vb infin] for | 11 |
|
