| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | which had been [verb] | 2021 |
|
| 2 | which had been [vb pp] | 1857 |
|
| 3 | [pron] had been built | 72 |
|
| 4 | which [verb] been built | 51 |
|
| 5 | which have been built | 51 |
|
| 6 | which had been build | 41 |
|
| 7 | which had [been] built | 35 |
|
| 8 | which [vb past] been built | 35 |
|
| 9 | which had [be] built | 35 |
|
| 10 | which had be built | 35 |
|
