| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | should be [vb pp] [adv] [to-vb] | 41 |
|
| 2 | should [be] [vb pp] [adv] [to-vb] | 41 |
|
| 3 | should be [vb pp] [adv] [to-vb] | 41 |
|
| 4 | should [be] [vb pp] [adv] to prevent | 5 |
|
| 5 | should [be] used [adv] [to-vb] | 5 |
|
