| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] [Wh adv] difficult it be for | 5 |
|
| 2 | [vb past] how difficult it [be] for | 5 |
|
| 3 | [vb past] [Wh adv] difficult it [be] for | 5 |
|
| 4 | [vb past] [Wh adv] difficult it [be] for | 5 |
|
