| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb mod] be heard [v-ing] | 58 |
|
| 2 | [modal v] be heard [v-ing] | 58 |
|
| 3 | could be heard [v-ing] | 44 |
|
| 4 | could be heard [v-ing] | 44 |
|
| 5 | can be heard [v-ing] | 9 |
|
| 6 | can be heard [v-ing] | 9 |
|
| 7 | [modal v] be heard saying | 6 |
|
