一定要熄了火，然后再离开。

Be sure to put out the fire before you leave.

Source: Tatoeba

Sentence Composition

1 一定要 yīdìngyào must
2 熄 xī
  1. to extinguish
  2. to put out (fire)
  3. to quench
  4. to stop burning
  5. to go out (of fire, lamp etc)
  6. to come to an end
  7. to wither away
  8. to die out
  9. Taiwan pr. xí
=3 了 le
  1. (completed action marker)
  2. (modal particle indicating change of state, situation now)
  3. (modal particle intensifying preceding clause)
=3 了 liǎo
  1. to finish
  2. (used with 得 dé or 不 bù after a verb to express (im)possibility, as in 忘不了 wàngbuliǎo "cannot forget")
  3. (literary) (usually followed by a negative such as 無 wú or 不 bù) completely (not); entirely (not); (not) in the least
  4. to understand clearly (variant of 瞭 liǎo)
=3 了 liǎo
  1. (of eyes) bright
  2. clear-sighted
  3. to understand clearly
=3 了 liào unofficial variant of 瞭 liào
=4 火 Huǒ surname Huo
=4 火 huǒ
  1. fire
  2. urgent
  3. ammunition
  4. fiery or flaming
  5. internal heat (Chinese medicine)
  6. hot (popular)
  7. classifier for military units (old)
  8. Kangxi radical 86
5 然后 ránhòu then; after that; afterwards
6 再 zài
  1. again; once more; re-
  2. further; beyond this point of time
  3. (before an adjective) more
  4. then (after sth, and not until then)
  5. no matter how ... (followed by an adjective or verb, and then (usually) 也 yě or 都 dōu for emphasis)
  6. (used to introduce additional information, as in 再則 zàizé, 再就是 zàijiùshì etc)
  7. (literary) to reappear; to reoccur
7 离开 líkāi to depart; to leave