Present perfect subjunctive
The present perfect subjunctive is formed by adding the past participle of the main verb to the present subjunctive of the auxiliary (avere or essere).
The typical literal translation of the present subjunctive is “may have” plus the meaning of the past participle of the main verb (che io abbia fatto — “that I may have done”; che tu sia partito — “that you may have left”).
Very often though, the “may have” need not be used. The translation must always depend on good English. For example, the sentence Mi dispiace che tu sia stato malato could be translated literally “I am sorry that you may have been ill,” but in modern standard English, one would say: “I am sorry (that) you were ill.”
The present perfect subjunctive has the same uses as the present subjunctive, except for the sequence of tenses.
Sono contento ch’egli stia bene. — I am glad that he is well.
Sono contenta ch’egli sia partito. — I am glad he left.
Vorrà ch’io vada con lei. — She will want me to go with her.
Digli che parli con Roberto! — Tell him to speak with Robert!
Non gli dica che te l’abbia detto io. — Don’t tell him that I told you.
Dubiterà ch’io sia uscito. — He will doubt that I went out.
Thus, as these examples show, a main verb in the present, future, or imperative may be followed by a verb in the present subjunctive or in the present perfect subjunctive. The present perfect subjunctive will be used whenever the action of the dependent clause is past in relation to the principal clause.
those (people) who
to err, to be mistaken
to shout, to cry
I am sorry