| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must [not/n't] be used | 28 |
|
| 2 | must not be used | 28 |
|
| 3 | must not be used | 26 |
|
| 4 | must [adv] be used | 21 |
|
| 5 | must only be used | 7 |
|
| 6 | must only be used | 7 |
|
