| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | if they [vb base] be [v-ing] | 15 |
|
| 2 | if they [vb base] been [v-ing] | 14 |
|
| 3 | if they [vb base] [been] [v-ing] | 14 |
|
| 4 | if they have [be] [v-ing] | 8 |
|
| 5 | if they 've [be] [v-ing] | 6 |
|
