| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb base] whether they [vb mod] [verb] | 15 |
|
| 2 | [vb base] whether they [modal v] [vb infin] | 15 |
|
| 3 | [vb base] whether they should [verb] | 5 |
|
| 4 | [vb base] whether they can [verb] | 5 |
|
| 5 | [vb base] whether they should [verb] | 5 |
|
| 6 | [vb base] whether they can [verb] | 5 |
|
