YOU SAID:

The bird flew across the sky

INTO JAPANESE

鳥は空を飛んでいった

BACK INTO ENGLISH

Birds flew the sky

INTO JAPANESE

鳥は空を飛んだ

BACK INTO ENGLISH

Birds flew in the sky.

INTO JAPANESE

鳥は空を飛んだ。

BACK INTO ENGLISH

The birds flew the sky.

INTO JAPANESE

鳥たちは空を飛んだ。

BACK INTO ENGLISH

The birds flew the sky.