| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [Wh adv] it [is] [verb] | 688 |
|
| 2 | [adv] it [is] [v-ing] | 655 |
|
| 3 | [Wh adv] [pron] [is] [v-ing] | 526 |
|
| 4 | [Wh adv] it [be] [v-ing] | 236 |
|
