| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | has been built up [prep] | 26 |
|
| 2 | has been built up over | 6 |
|
| 3 | has been built up by | 6 |
|
| 4 | has been built up by | 6 |
|
| 5 | has been built up over | 6 |
|
