| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [adv] be [v-ing] [prep] [art] | 7 |
|
| 2 | could [adv] [be] [v-ing] [prep] [art] | 7 |
|
| 3 | could [adv] [be] [v-ing] [prep] a | 5 |
|
