| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | once or [adv] a [noun] [prep] | 17 |
|
| 2 | once [conj] [adv] a [noun sg] [prep] | 17 |
|
| 3 | once [conj] [adv] a [noun] [prep] | 17 |
|
| 4 | once [conj] [adv] a [noun] [prep] | 17 |
|
| 5 | once or [adv] a [noun] [prep] | 17 |
|
| 6 | once [coord] [adv] a [noun] [prep] | 17 |
|
| 7 | once [conj] twice a [noun] [prep] | 16 |
|
| 8 | once [conj] [adv] a week [prep] | 9 |
|
| 9 | once [conj] [adv] a week [prep] | 9 |
|
| 10 | once [conj] [adv] a year [prep] | 5 |
|
| 11 | once [conj] [adv] a year [prep] | 5 |
|
