| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun sg] [v-ing] [prep] an | 469 |
|
| 2 | [noun sg] when [v-ing] [prep] | 363 |
|
| 3 | when [v-ing] [prep] an | 29 |
|
| 4 | [noun sg] when [v-ing] an | 21 |
|
