| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb mod] have [been] [v-ing] [prep] | 288 |
|
| 2 | it [vb mod] have [been] [prep] | 230 |
|
| 3 | it have [been] [v-ing] [prep] | 131 |
|
| 4 | it [vb mod] have [been] [v-ing] | 45 |
|
