| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb base] been used [prep] a | 15 |
|
| 2 | have been use [prep] a | 15 |
|
| 3 | [vb base] been use [prep] a | 13 |
|
| 4 | [vb base] been use as a | 9 |
|
