| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | had happened | 1782 |
|
| 2 | has happened | 1035 |
|
| 3 | 's happened | 759 |
|
| 4 | have happened | 619 |
|
| 5 | to have happened | 97 |
|
| 6 | have happened | 90 |
|
| 7 | 've happened | 9 |
|
| 8 | having happened | 8 |
|
| 9 | 'd happened | 6 |
|
