| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must [verb] to | 1036 |
|
| 2 | [modal v] return to | 643 |
|
| 3 | [vb mod] return to | 643 |
|
| 4 | must return [prep] | 45 |
|
| 5 | must return to | 40 |
|
