| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it is [adv] [vb pp] [prep] | 1421 |
|
| 2 | is [adv] often [vb pp] [prep] | 111 |
|
| 3 | it is often [vb pp] [prep] | 102 |
|
| 4 | it is [adv] often [vb pp] | 32 |
|
