| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be a difficult time | 20 |
|
| 2 | [be] a difficult time | 20 |
|
| 3 | [is] a difficult time | 8 |
|
| 4 | [was/were] a difficult time | 6 |
|
| 5 | was a difficult time | 6 |
|
| 6 | is a difficult time | 6 |
|
