| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] [adv] happen to | 32 |
|
| 2 | [vb past] [adv] happened to | 30 |
|
| 3 | had [adv] happen to | 30 |
|
| 4 | [vb past] ever happen to | 12 |
|
| 5 | [vb past] never happen to | 8 |
|
