| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] about 20 | 143 |
|
| 2 | of about 20 | 45 |
|
| 3 | for about 20 | 41 |
|
| 4 | to about 20 | 24 |
|
| 5 | by about 20 | 10 |
|
| 6 | at about 20 | 7 |
|
| 7 | from about 20 | 6 |
|
