| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [be] a number of [noun] [prep] | 345 |
|
| 2 | [be] a [noun] of problem [prep] | 21 |
|
| 3 | [be] a number of problem [prep] | 16 |
|
| 4 | [be] [art] number of problem [prep] | 16 |
|
| 5 | [be] a number [prep] problem [prep] | 16 |
|
| 6 | [be] a number [prep] problem [prep] | 16 |
|
