| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be doubtful [subord] the [noun sg] | 24 |
|
| 2 | is doubtful [subord] [art] [noun sg] | 22 |
|
| 3 | be doubtful whether [art] [noun sg] | 16 |
|
| 4 | be doubtful if [art] [noun sg] | 13 |
|
| 5 | was doubtful [subord] [art] [noun sg] | 5 |
|
