| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | had [not/n't] known | 235 |
|
| 2 | [not/n't] known [prep] | 229 |
|
| 3 | had known [prep] | 176 |
|
| 4 | had [not/n't] [prep] | 109 |
|
