| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb pp] [adv] [art] | 3204 |
|
| 2 | [vb pp] to ensure [art] | 100 |
|
| 3 | [adv] to ensure [art] | 44 |
|
| 4 | [vb pp] [adv] to ensure | 34 |
|
