| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could be [vb pp] [adv prt] [prep] | 388 |
|
| 2 | could be [vb pp] [v-ing] [prep] | 65 |
|
| 3 | be [vb pp] [v-ing] [adv prt] [prep] | 37 |
|
| 4 | could be [v-ing] [adv prt] [prep] | 21 |
|
| 5 | could be [vb pp] [v-ing] [adv prt] | 11 |
|
