aux: auxiliary
An auxiliary of a clause is a non-main verb of the clause, e.g., a modal auxiliary, or a form of be, do or have in a periphrastic tense.
Exception: Auxiliary verb used to construct the passive
voice is not labeled aux but auxpass.
Reagan has died
aux(died-3, has-2)
He should leave
aux(leave-3, should-2)
Do you think that he will have left when we come ?
aux(think, Do)
aux(left, will)
aux(left, have)
aux in other languages: [bg] [cs] [de] [el] [en] [es] [eu] [fa] [fi] [fr] [ga] [he] [hu] [it] [ja] [ko] [sv] [u]