| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] an [noun] | 60397 |
|
| 2 | [prep] an [noun pl] | 380 |
|
| 3 | [prep] [art] officers | 323 |
|
| 4 | [prep] [art] officers | 323 |
|
| 5 | [prep] an officer | 196 |
|
| 6 | [prep] a officers | 6 |
|
