Breakdown of Il a répondu que son ami était célibataire.
être
to be
il
he
l'ami
the friend (m)
avoir
to have
Questions & Answers about Il a répondu que son ami était célibataire.
If the friend is still single right now, why do we use the past tense était?
In French reported speech, if the reporting verb (a répondu) is in a past tense, the verb in the reported clause must shift back in time, even if the fact is still true today. The original present tense statement ("mon ami est célibataire") shifts to the imparfait (était). This is the sequence of tenses rule.
Can we drop que like we often drop "that" in English?
No, in French, the conjunction que is strictly required to connect the two clauses. Unlike in English where you can just say "He answered his friend was single," you can never drop que in French.
Does son ami only mean "his friend", or could it mean "her friend"?
How would the spelling of célibataire change if the friend were female?
It wouldn't change at all! Adjectives that already end in an unaccented -e in their masculine form, like célibataire, stay exactly the same in the feminine form. If the friend were a woman, you would just write son amie était célibataire.