Learn Turkish: Temmuz ayında karnavala ailece katıldık. - We attended the carnival as a family in July.

The suffix -ce attaches to aile (family) to create the adverb ailece. It means "as a whole family" or "collectively as a family." While you could also say aile olarak (as a family), using -ce strongly emphasizes that the entire group participated together as one collective entity.

Why does karnaval take the dative suffix -a here?

The verb katılmak (to join, to attend, to participate) always governs the dative case. It focuses on the event you are joining or entering into. Therefore, "attending the carnival" must be expressed as karnavala katıldık (literally "joined to the carnival").

Could I just say Temmuzda instead of Temmuz ayında?

Yes, Temmuzda (in July) is completely correct and very common. However, adding ayı (month) to form the noun compound Temmuz ayı before adding the locative case (-nda) is a natural stylistic choice in Turkish. It sounds slightly more structured or formal, similar to saying "in the month of July" in English.

Why is ailece placed immediately before the verb?

In Turkish, the word placed right before the verb carries the primary focus of the sentence. By putting ailece there, the speaker specifically emphasizes how they attended (together as a family) rather than when or what they attended.