| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have been an [adj] part | 25 |
|
| 2 | has [been] an [adj] part | 16 |
|
| 3 | have [been] an important part | 10 |
|
| 4 | have [been] an integral part | 5 |
|
| 5 | had [been] an [adj] part | 5 |
|
