| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | problems [Wh det] [vb mod] have [been] | 5 |
|
| 2 | problems [Wh det] [vb mod] have [be] | 5 |
|
| 3 | problems [Wh det] [vb mod] have been | 5 |
|
| 4 | problems which [vb mod] have [be] | 5 |
|
| 5 | problems [Wh det] [vb mod] have be | 5 |
|
