| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [v-ing] [noun] [prep] a time [Wh adv] | 9 |
|
| 2 | [v-ing] [noun] [prep] a time when | 9 |
|
| 3 | [v-ing] [noun] at a time [Wh adv] | 8 |
|
| 4 | [v-ing] [noun] at a time [Wh adv] | 8 |
|
