| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | which [vb mod] be difficult | 44 |
|
| 2 | which [vb mod] be difficult | 44 |
|
| 3 | which would be difficult | 16 |
|
| 4 | which may be difficult | 11 |
|
| 5 | which can be difficult | 10 |
|
