Other semi-auxiliaries

The other semi-auxiliaries all select for the infinitival form of the verb. Many of these auxiliaries allow for DO-support and can appear in both base and past participle forms, in addition to being able to stand alone (indicative mode). Examples of this type appear below.

(414)0(414

(415)

Alex used to attend karate workshops .  (415)0(415

(416)

Angelina might have used to believe in fate .  (416)0(416

(417)

Rich did not used to want to be a physical therapist .  (417)0(417

(418)

Mick might not have to play the game tonight .  (418)0(418

(419)

Singer had to have been there .  (419)0(419

(420)

Heather has got to finish that project before she goes insane . 

The auxiliaries ought to and BE to may not be preceded by any other auxiliary.

(420)0(420

(421)

Biff ought to have been working harder .  (421)0(421

(422)

Carson does ought to have been working harder .  (422)0(422

(423)

the party is to take place this evening .  (423)0(423

(424)

the party had been to take place this evening . 

The trickiest element in this group of auxiliaries is used to. While the other verbs behave according to standard inflection for auxiliaries, used to has the same form whether it is in mode base, past participle, or indicative forms. The only connection used to maintains with the infinitival form use is that occasionally, the bare form use will appear with DO-support. Since the three modes mentioned above are mutually exclusive in terms of both the morphology and the lexicon, used has three entries in each.