凡是…都…: all, every (without exception)
固定格式 / set structures
Tone colorsā tone 1á tone 2ǎ tone 3à tone 4a neutral
凡是 + N/relative clause (的)，都 + V
凡是 ("all that, whoever") covers every member of a category, without exception. It states a general rule: 凡是…的，都….
It opens the sentence and requires 都 afterwards. Formal register: regulations, principles, sayings.
Examples
凡是能回收的垃圾，都要放进蓝色的桶里。
Fánshì néng huíshōu de lājī, dōu yào fàng jìn lánsè de tǒng lǐ.All recyclable waste must go in the blue bin.
凡是参加比赛的人，都可以得到一份礼物。
Fánshì cānjiā bǐsài de rén, dōu kěyǐ dédào yí fèn lǐwù.Everyone who takes part gets a gift.
凡是他答应的事，都一定会做到。
Fánshì tā dāying de shì, dōu yídìng huì zuò dào.Whatever he promises, he always delivers.
Common mistakes
✗ 凡是参加的人可以得到礼物 → ✓ …都可以… (都 required).
✗ 凡是 + a single individual: ✗ 凡是我哥哥… → 凡是 covers a category.