| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | had been [v-ing] [prep] | 1917 |
|
| 2 | been [v-ing] [prep] [noun] | 1487 |
|
| 3 | had been [prep] [noun] | 1251 |
|
| 4 | had been [v-ing] [noun] | 490 |
|
