YOU SAID:

I think the party's downstairs

INTO JAPANESE

パーティーは階下で行われると思う

BACK INTO ENGLISH

I think the party is going on downstairs.

INTO JAPANESE

階下でパーティーが行われているようです。

BACK INTO ENGLISH

There seems to be a party going on downstairs.

INTO JAPANESE

階下でパーティーが行われているようです。

BACK INTO ENGLISH

There seems to be a party going on downstairs.