| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must be [verb] at the [noun] | 52 |
|
| 2 | must [be] [verb] at the [noun sg] | 50 |
|
| 3 | must [be] [vb pp] at the [noun] | 49 |
|
| 4 | must [be] [verb] at the outset | 13 |
|
| 5 | must [be] [verb] at the outset | 13 |
|
| 6 | must [be] [verb] at the time | 10 |
|
| 7 | must [be] [verb] at the time | 10 |
|
| 8 | must [be] [verb] at the end | 6 |
|
| 9 | must [be] [verb] at the end | 6 |
|
