| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] how difficult it [be] for | 20 |
|
| 2 | [verb] how difficult it be for | 20 |
|
| 3 | [verb] how difficult it [be] for | 20 |
|
| 4 | [verb] how difficult it [is] for | 13 |
|
| 5 | [verb] how difficult it is for | 13 |
|
| 6 | [verb] how difficult it [was/were] for | 7 |
|
| 7 | [verb] how difficult it was for | 7 |
|
| 8 | [vb base] how difficult it [be] for | 7 |
|
| 9 | know how difficult it [be] for | 5 |
|
| 10 | [vb past] how difficult it [be] for | 5 |
|
| 11 | know how difficult it [be] for | 5 |
|
