| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | how difficult it [be] for [noun pl] | 7 |
|
| 2 | how difficult it be for [noun pl] | 7 |
|
| 3 | how difficult it [be] for [noun pl] | 7 |
|
| 4 | how difficult it is for [noun pl] | 6 |
|
| 5 | how difficult it [is] for [noun pl] | 6 |
|
