| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | had [been] empty for [det] | 6 |
|
| 2 | had [be] empty for [det] | 6 |
|
| 3 | had been empty for [det] | 6 |
|
| 4 | had be empty for [det] | 6 |
|
