| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | to prevent [pron] [v-ing] [adv] | 21 |
|
| 2 | to prevent [pron] [verb] [adv] | 21 |
|
| 3 | to prevent [pron] happen [adv] | 7 |
|
| 4 | to prevent [pron] happening [adv] | 7 |
|
| 5 | to prevent [pron] [adv] [v-ing] | 5 |
|
| 6 | to prevent [pron] [adv] [verb] | 5 |
|
