| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | should be [verb] [prep] | 9907 |
|
| 2 | [modal v] be concentrate [prep] | 76 |
|
| 3 | should be concentrate [prep] | 21 |
|
| 4 | should [be] concentrate [prep] | 21 |
|
| 5 | should [be] concentrate [prep] | 21 |
|
