| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [conj] they could hear [pron] | 5 |
|
| 2 | they could [adv] hear [pron] | 11 |
|
| 3 | they could not hear [pron] | 7 |
|
| 4 | they could [not/n't] hear [pron] | 7 |
|
| 5 | they could n't hear [pron] | 6 |
|
| 6 | they could hear [pron] [verb] | 9 |
|
| 7 | they could hear [pron] [v-ing] | 8 |
|
