| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] concentrate on | 384 |
|
| 2 | concentrate on [noun sg] | 378 |
|
| 3 | [modal v] on [noun sg] | 77 |
|
| 4 | [modal v] concentrate [noun sg] | 7 |
|
