As the term would suggest, semi-deponent verbs display an unusual feature in that one part of the verb is deponent but the other parts are not. There are not many of these, they do not often occur, and the three most common I have placed first in the list; look at the third part listed
audeō, audēre, ausus sum (2): dare
gaudeō, gaudēre, gāvīsus sum (2): be glad; rejoice
soleō, solēre, solitus sum (2): be accustomed
cōnfīdō, cōnfīdere, cōnfīsus sum (3): trust
diffīdō, diffīdere, diffīsus sum (3): distrust
fīdō, fīdere, fīsus sum (3): to trust
[i] the present, imperfect and future tenses are conjugated like any other verb i.e. they are not deponent
gaudeō, gaudēs, gaudet etc. │ I rejoice, you (sg.) rejoice, he / she rejoices etc.
gaudēbam, gaudēbās etc. │ I was rejoicing, you (sg.) used to rejoice etc.
gaudēbō etc. │ I shall rejoice etc.
[ii] It is the perfect tense forms that are deponent i.e. there is no separate, single perfect tense form for these verbs; they are formed in exactly the same way as the perfect passive and perfect of other deponent verbs
gavisus, -a sum│ I (have) rejoiced i.e. the perfect tense is passive in form but has an active meaning
gavisi, -ae sumus / sunt │ we / they (have) rejoiced
ausus, -a es │ you (sg.) (have) dared
ausus, -a est │ (s)he (has) dared
ausi, -ae estis│ you (pl.) have dared
ausus erat │ he had dared i.e. the pluperfect tense form is passive but has an active meaning
Examples of perfect and pluperfect forms from the authors:
[1] audeō, audēre, ausus sum (2): dare
- non sine causa igitur Epicurus ausus est [perfect] dicere semper in pluribus bonis esse sapientem (Cicero) │ It is not without reason , therefore, that Epicurus ventured to say that he is always wise in many good things
- nunc, quia tantum ausi estis [perfect] sponte vestra … (Livy) │Now since you have dared so much of your own accord, …
- Ausus eram [pluperfect], memini, caelestia dicere bella (Ovid) │ I remember, I had dared to speak about celestial war
- et nec enim restitere Armenii, fuso qui proelium ausus erat [pluperfect] Demonacte praefecto (Tacitus) │ and the Armenians made no resistance after their governor, Demonax, had ventured on a battle and had been routed.
[2] gaudeō, gaudēre, gāvīsus sum (2): be glad; rejoice
- cognita morte C. Treboni non plus gavisus sum [perfect] quam dolui. (Cicero) │When I heard of the death of Caius Trebonius, I did not more rejoice than grieve.
- Videntes autem stellam gavisi sunt [perfect] gaudio magno valde (Vulgate) │ Seeing the star [= when they saw the star], they rejoiced with a very great joy
[3] soleō, solēre, solitus sum (2): be accustomed; be in the habit (of doing something)
- … tibi solitus sum [perfect] dicere magis te fortem accusatorem mihi videri quam sapientem candidatum (Cicero) │ … I have often said [i.e. I have often been accustomed to say(ing)] to you that you appeared to me to be a brave senator rather than a wise candidate.
- quos ubi et propius accedere et plures quam soliti erant [pluperfect] Celtiberi conspexerunt, … (Livy) │ When the Celtiberi saw them approaching more closely and in greater strength than they had usually done …
