| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | they happened to be [verb] | 8 |
|
| 2 | they happened to be [v-ing] | 6 |
|
| 3 | [conj] they happened to be | 11 |
|
| 4 | [subord] they happened to be | 8 |
|
