| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | problem [is] [adv] | 558 |
|
| 2 | [prep] [is] [adv] | 343 |
|
| 3 | [prep] problem [adv] | 53 |
|
| 4 | [prep] problem [is] | 22 |
|
