| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] a [adj] contribution to | 401 |
|
| 2 | [be] a [adj] contribution to | 40 |
|
| 3 | [be] [verb] a [adj] contribution | 23 |
|
| 4 | [be] [verb] a contribution to | 5 |
|
