| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | had [adv] heard of | 140 |
|
| 2 | had [not/n't] heard of | 47 |
|
| 3 | had [not/n't] [adv] heard | 20 |
|
| 4 | [not/n't] [adv] heard of | 10 |
|
