| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] have served as [art] [noun] | 10 |
|
| 2 | [vb mod] have served as [art] [noun] | 10 |
|
| 3 | have served as [art] [noun] [prep] | 8 |
|
| 4 | have served as [art] [noun] [prep] | 8 |
|
