| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | how difficult it [modal v] be | 25 |
|
| 2 | how difficult it [vb mod] [be] | 25 |
|
| 3 | how difficult it [modal v] [be] | 25 |
|
| 4 | how difficult it [modal v] be | 25 |
|
| 5 | how difficult it can [be] | 9 |
|
| 6 | how difficult it would [be] | 9 |
|
| 7 | how difficult it can [be] | 9 |
|
| 8 | how difficult it would [be] | 9 |
|
