| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be [vb pp] for a [noun] | 272 |
|
| 2 | must be [vb pp] for [noun] | 49 |
|
| 3 | must be [vb pp] a [noun] | 21 |
|
| 4 | must be [vb pp] for a | 14 |
|
