| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | type [prep] [noun] must be [vb pp] | 10 |
|
| 2 | type of [noun] must be [verb] | 10 |
|
| 3 | type [prep] [noun sg] must be [verb] | 9 |
|
| 4 | type [prep] [noun] must be [verb] | 6 |
|
