| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] was [vb pp] at a [noun] | 153 |
|
| 2 | [noun] was [vb pp] at a [noun sg] | 143 |
|
| 3 | [noun] [be] [vb pp] at a concentration | 8 |
|
| 4 | [noun] [was/were] [vb pp] at a concentration | 8 |
|
| 5 | [noun] be [vb pp] at a concentration | 8 |
|
| 6 | [noun] was [vb pp] [prep] a concentration | 7 |
|
| 7 | [noun] was [vb pp] [prep] a concentration | 7 |
|
| 8 | [noun] was [vb pp] at a concentration | 6 |
|
| 9 | [noun] was [vb pp] at a concentration | 6 |
|
| 10 | [noun] was [vb pp] at [art] concentration | 6 |
|
| 11 | [noun] was [vb pp] at a concentration | 6 |
|
| 12 | [noun] was [verb] at a concentration | 6 |
|
| 13 | [noun] was [vb pp] at [art] concentration | 6 |
|
