| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have occurred | 1622 |
|
| 2 | [vb -s] occurred | 566 |
|
| 3 | has occurred | 561 |
|
| 4 | had occurred | 389 |
|
| 5 | [vb past] occurred | 389 |
|
| 6 | [vb base] occurred | 282 |
|
| 7 | have occurred | 278 |
|
| 8 | [vb infin] occurred | 261 |
|
| 9 | have occurred | 260 |
|
| 10 | [to-vb] occurred | 113 |
|
| 11 | to have occurred | 112 |
|
| 12 | having occurred | 20 |
|
| 13 | [v-ing] occurred | 20 |
|
