| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] how it happen | 25 |
|
| 2 | know how it happen | 17 |
|
| 3 | [be] how it happen | 15 |
|
| 4 | be how it happen | 15 |
|
| 5 | [is] how it happen | 13 |
|
| 6 | [adv] how it happen | 13 |
|
| 7 | [adv] how it happen | 12 |
|
| 8 | [vb infin] how it happen | 11 |
|
| 9 | 's how it happen | 8 |
|
| 10 | know how it happen | 8 |
|
| 11 | exactly how it happen | 5 |
|
| 12 | exactly how it happen | 5 |
|
| 13 | is how it happen | 5 |
|
| 14 | how [verb] it happen | 50 |
|
| 15 | how do it happen | 40 |
|
| 16 | how [vb past] it happen | 39 |
|
| 17 | how did it happen | 34 |
|
| 18 | how [vb -s] it happen | 9 |
|
| 19 | how have it happen | 8 |
|
| 20 | how does it happen | 6 |
|
| 21 | how [vb mod] it happen | 5 |
|
| 22 | how [modal v] it happen | 5 |
|
| 23 | how had it happen | 5 |
|
| 24 | how it [verb] happen | 19 |
|
| 25 | how it have happen | 18 |
|
| 26 | how it [vb past] happen | 17 |
|
| 27 | how it had happen | 16 |
|
| 28 | how it [vb mod] happen | 10 |
|
| 29 | how it [modal v] happen | 10 |
|
| 30 | how it happen [pron] | 8 |
|
