| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [num] level of [noun] [prep] [art] | 12 |
|
| 2 | [num] level of [noun] [prep] the | 11 |
|
| 3 | [num] levels of [noun] [prep] [art] | 10 |
|
| 4 | [num] level of [noun sg] [prep] [art] | 10 |
|
