The volitional form of the auxiliary verb was briefly introduced before when we looked at the volitional.
| Form | Dictionary | Volitional |
| Polite | です | でしょう |
| Standard | だ | だろう |
The volitional for verbs translated as let’s in English; however, for the auxiliary verb the nuance is actually one of supposition.
| この |
| Solving this problem is impossible. |
| この |
| This problem isn’t likely to be solved. |
Both standard and polite forms can be added directly to the end of verbs.
| If she tried I reckon she could do it. |
| If Saori says she’ll join the study group, I bet he will come, too. |
The volitional form of the standard copula can also be added directly to i-adjectives.
| それは |
| I bet that’s difficult. |
The な particle here is a more masculine ending particle.
Used as a question, でしょうか is also more polite than ですか (again, it has the nuance of “wondering” if something might be okay).
| I wondering if I may ask something personal? |
In fact, we can add a further degree of certainty to this form by removing the う from both the standard and polite forms of the volitional copula.
| You’re going to school tomorrow, right? |
| やったのはお |
| You’re the one who did it! |
お前 is a very derogatory way of saying “you”. When this abbreviated form (だろ) is used with the standard form of the volitional it has almost an accusatory tone. In the last example, you know that he’s the one who did it, you just want him to admit it. It has quite a masculine nuance.