| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must [verb] their | 290 |
|
| 2 | must know [pron] | 141 |
|
| 3 | [modal v] know their | 19 |
|
| 4 | [vb mod] know their | 19 |
|
| 5 | must know [pos pn] | 15 |
|
| 6 | must know their | 5 |
|
| 7 | must know their | 5 |
|
