| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] [prep] [be] a | 564 |
|
| 2 | must [prep] [be] [art] | 23 |
|
| 3 | must [prep] [be] [art] | 23 |
|
| 4 | must [prep] [be] a | 18 |
|
| 5 | must [prep] [be] a | 16 |
|
