| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [conj] once [conj] [adv] a | 7 |
|
| 2 | [conj] once [conj] twice a | 7 |
|
| 3 | [conj] once [conj] [adv] a | 7 |
|
| 4 | [conj] once or [adv] a | 7 |
|
| 5 | [conj] once [coord] [adv] a | 7 |
|
| 6 | [conj] once or [adv] a | 7 |
|
