| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] how difficult it is for | 13 |
|
| 2 | know how [adj] it is for | 9 |
|
| 3 | know how difficult it is [prep] | 6 |
|
| 4 | know how difficult [pron] is for | 5 |
|
| 5 | know how difficult it is for | 5 |
|
| 6 | know how difficult it [be] for | 5 |
|
| 7 | know how difficult [pers pn] is for | 5 |
|
| 8 | know how difficult it [is] for | 5 |
|
| 9 | know [adv] difficult it is for | 5 |
|
| 10 | know how difficult it be for | 5 |
|
