| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it is [vb pp] that about [num] | 7 |
|
| 2 | it is [verb] that about [num] | 7 |
|
| 3 | it is estimated that about [num] | 6 |
|
| 4 | it is estimate that about [num] | 6 |
|
