| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [be] [v-ing] [prep] | 71147 |
|
| 2 | it [be] [prep] | 23930 |
|
| 3 | it [be] [v-ing] | 10696 |
|
| 4 | it [v-ing] [prep] | 589 |
|
