| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [subord] it [is] [adv] [verb] | 836 |
|
| 2 | [conj] it [is] [adv] [v-ing] | 301 |
|
| 3 | [subord] [pron] [is] [adv] [v-ing] | 245 |
|
| 4 | [subord] it [is] [adv] [v-ing] | 189 |
|
| 5 | [subord] it [be] [adv] [v-ing] | 136 |
|
