YOU SAID:

this party is gonna crash very fast

INTO JAPANESE

このパーティーは非常に速くクラッシュするつもりです

BACK INTO ENGLISH

This party is going to crash very quickly

INTO JAPANESE

このパーティーは非常に迅速にクラッシュするだろう

BACK INTO ENGLISH

This party will crash very quickly

INTO JAPANESE

このパーティーは非常に速くクラッシュするでしょう

BACK INTO ENGLISH

This party will crash very quickly