| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | problems that [vb mod] be | 27 |
|
| 2 | problems that [vb mod] [be] | 27 |
|
| 3 | problems that may [be] | 7 |
|
| 4 | problems that will [be] | 5 |
|
