| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb -s] a key role [prep] | 30 |
|
| 2 | [vb -s] a key role [prep] | 30 |
|
| 3 | [vb -s] a key role in | 26 |
|
| 4 | plays a key role [prep] | 20 |
|
| 5 | has a key role [prep] | 7 |
|
