YOU SAID:
What happened 18 months prior to your study?
INTO JAPANESE
研究の18か月前に何が起こりましたか?
BACK INTO ENGLISH
What happened 18 months before the study?
INTO JAPANESE
研究の18か月前に何が起こったのでしょうか?
BACK INTO ENGLISH
What happened 18 months before the study?
Come on, you can do better than that.