YOU SAID:

Don't know why they building forts they about to go night night!

INTO JAPANESE

彼らが夜の夜に行くことを約束する理由を知らないでください！

BACK INTO ENGLISH

Do not know the reasons they promise to go at night!

INTO JAPANESE

彼らが夜に行くことを約束する理由を知らない！

BACK INTO ENGLISH

I do not know the reasons they promise to go at night!

INTO JAPANESE

彼らが夜に行くことを約束した理由はわかりません！

BACK INTO ENGLISH

I do not know why they promised to go at night!

INTO JAPANESE

なぜ彼らが夜に行くと約束したのかわからない！

BACK INTO ENGLISH

I do not know why they promised to go at night!