| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | they [vb past] [prep] a time | 9 |
|
| 2 | they [vb past] [prep] a time | 8 |
|
| 3 | they [vb past] at a time | 5 |
|
| 4 | they [vb past] at a time | 5 |
|
