| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | is [adv] [v-ing] [prep] a | 205 |
|
| 2 | it is [adv] [v-ing] [prep] | 146 |
|
| 3 | it is [adv] [prep] a | 87 |
|
| 4 | it is [v-ing] [prep] a | 51 |
|
| 5 | it is [adv] [v-ing] a | 34 |
|
