Following are a number of back-translations as well as a sample translation for translators of Ecclesiastes 3:15:

• Kupsabiny: “The matter/thing that has already happened today, is what happened long ago,
  and what will happen, is what was (before).
  What God has done will come round again.” (Source: Kupsabiny Back Translation)
• Newari: “What exists in this world, has been here before,
  and what will be has also already been.
  God will take account of the work that has already been done before.” (Source: Newari Back Translation)
• Hiligaynon: “What is-happening now and what will-happen later has- already-happened in-time-past. God just repeats the/what is-happening.” (Source: Hiligaynon Back Translation)
• English: “Things that exist now have already existed previously,
  and things that will happen in the future have already happened previously;
  God causes the same things to happen many times.” (Source: Translation for Translators)