È l'unico traguardo che lui abbia mai raggiunto.
It is the only achievement that he has ever reached.
Breakdown of È l'unico traguardo che lui abbia mai raggiunto.
essere
to be
lui
he
avere
to have
mai
ever / never
Questions & Answers about È l'unico traguardo che lui abbia mai raggiunto.
Why do we use the subjunctive abbia raggiunto instead of the indicative ha raggiunto here?
The word l'unico (the only) sets up an absolute limit. In Italian, when a relative clause (the part starting with che) describes a noun modified by an extreme limit like 'the only', 'the first', or 'the last', it triggers the subjunctive mood.
What tense is abbia raggiunto?
This is the past subjunctive (congiuntivo passato). You form it by taking the present subjunctive of the helper verb (here, avere becomes abbia) and adding the past participle of the main verb (raggiungere becomes raggiunto).
Is it mandatory to include the subject pronoun lui in this sentence?
No, it could be dropped. However, using lui helps avoid confusion because the singular present subjunctive forms of avere are all exactly the same: io abbia, tu abbia, and lui/lei abbia. It also adds a bit of emphasis, highlighting that it is the only achievement he has reached.
Why is mai placed right in the middle of the verb?