| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [was/were] [verb] at about [num] | 15 |
|
| 2 | [was/were] [verb] at about [num] | 15 |
|
| 3 | was [verb] at about [num] | 14 |
|
| 4 | [was/were] [vb pp] at about [num] | 11 |
|
| 5 | [was/were] estimated at about [num] | 5 |
|
| 6 | [was/were] estimate at about [num] | 5 |
|
