| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] [adv] [vb infin] [pron] happened to | 8 |
|
| 2 | [modal v] not [vb infin] [pron] happened to | 5 |
|
| 3 | [modal v] [not/n't] [vb infin] [pron] happened to | 5 |
|
| 4 | [modal v] [vb infin] [verb] [pron] happened to | 6 |
|
