| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] it [adv] difficult [verb] | 68 |
|
| 2 | i [vb past] it [adv] [verb] | 26 |
|
| 3 | i [vb past] it difficult [verb] | 16 |
|
| 4 | i [vb past] it [adv] difficult | 10 |
|
