| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | who have once [vb pp] [prep] | 12 |
|
| 2 | [Wh pn] have once [vb pp] [prep] | 12 |
|
| 3 | [Wh pn] had once [vb pp] [prep] | 11 |
|
| 4 | [Wh pn] have once [vb pp] in | 5 |
|
| 5 | [Wh pn] have once [vb pp] in | 5 |
|
