| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be [v-ing] [prep] a | 6861 |
|
| 2 | be not [v-ing] [prep] | 2294 |
|
| 3 | be not [prep] a | 435 |
|
| 4 | be not [v-ing] a | 289 |
|
| 5 | not [v-ing] [prep] a | 210 |
|
