Breakdown of Faccio tutto senza che lui interferisca.
lui
he
tutto
everything
fare
to do / to make
senza che
without (+ clause)
Questions & Answers about Faccio tutto senza che lui interferisca.
Why do we use the subjunctive interferisca after senza che?
The phrase senza che means "without". In Italian, conjunctions that introduce a condition or an action that is prevented or hypothetical—like senza che, prima che, or a condizione che—always trigger the subjunctive mood.
Why is the subject pronoun lui included? Couldn't we just say senza che interferisca?
You could leave it out if the context made it obvious, but lui is used here to prevent ambiguity. In the present subjunctive, the forms for I, you, and he/she/it are identical (interferisca). Adding lui clarifies that "he" is the one who might interfere.
What is the infinitive of interferisca, and why is there an "-isc-" in the middle?
The infinitive is interferire (to interfere). It is one of the regular "-ire" verbs that take an "-isc-" insert. Just as you say lui interferisce in the normal present tense, you must keep the "-isc-" in the present subjunctive for the singular forms and the "loro" form.
How would this sentence change if I wanted to say "I do everything without interfering" (meaning I am the one not interfering)?