| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | to prevent it [prep] [verb] [prep] | 6 |
|
| 2 | to prevent it [prep] [v-ing] [prep] | 6 |
|
| 3 | to prevent it from [verb] [prep] | 6 |
|
| 4 | to prevent it [prep] [verb] [prep] | 6 |
|
