| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] a [noun sg] [prep] | 30439 |
|
| 2 | once a [noun sg] [prep] | 300 |
|
| 3 | once [vb past] a [noun sg] | 152 |
|
| 4 | once [vb past] [noun sg] [prep] | 26 |
|
