| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb base] it [vb mod] not happen | 6 |
|
| 2 | [vb base] it [vb mod] [not/n't] happen | 6 |
|
| 3 | [vb base] it [vb mod] n't happen | 5 |
|
