Must be starving. ("I think it is almost a certainty that you are starving.") deontic: You must

normal verb
modal verb
affirmative	he works	he can work
negation	he does not work	he cannot work
emphatic	he does work hard	he can work hard
question	does he work here?	can he work at all?
negation + question	does he not work here?	can he not work at all?

Some form of auxiliary "do" occurs in all West Germanic languages except Afrikaans.^[5] Its occurrence in the Frisian languages is restricted to Saterland Frisian, where it may be a loan from Low German.^[6] In both German and Dutch, the construction has been known since the Middle Ages and is common in dialects, but is considered ungrammatical in the modern standard language.^[7] The Duden lists the following three potential uses of tun (to do) in modern German, with only the first being considered standard:^[8]