| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | once [verb] as a [noun sg] | 28 |
|
| 2 | once [vb pp] as a [noun sg] | 20 |
|
| 3 | once [vb past] as a [noun sg] | 7 |
|
| 4 | once work as a [noun sg] | 5 |
|
