| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb mod] to be | 4612 |
|
| 2 | used to be | 2738 |
|
| 3 | used to be | 2738 |
|
| 4 | ought to be | 1859 |
|
| 5 | ought to be | 1859 |
|
