| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [is] [verb] [modal v] | 433 |
|
| 2 | [is] [verb] [vb mod] | 433 |
|
| 3 | [be] [verb] must | 145 |
|
| 4 | [is] [verb] must | 44 |
|
