| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must be serve [prep] [det] [noun] | 8 |
|
| 2 | must be served [prep] [det] [noun] | 8 |
|
| 3 | must be serve on [det] [noun] | 8 |
|
| 4 | must be serve [prep] [det] [noun pl] | 7 |
|
| 5 | must be serve [prep] all [noun] | 7 |
|
