| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have been [det] improvement | 9 |
|
| 2 | [verb] been [det] improvement | 9 |
|
| 3 | [vb -s] been [det] improvement | 7 |
|
| 4 | has been [det] improvement | 6 |
|
| 5 | been [det] improvement [prep] | 8 |
|
| 6 | been [det] improvement [prep] | 8 |
|
| 7 | been [det] improvement in | 7 |
|
| 8 | been [det] improvement in | 7 |
|
