| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [conj] [vb past] [verb] [conj] | 591 |
|
| 2 | [conj] [vb past] [to-vb] [conj] | 297 |
|
| 3 | [conj] [verb] to ensure [conj] | 41 |
|
| 4 | [conj] [vb past] ensure [conj] | 12 |
|
