YOU SAID:

the birds are singing a song

INTO JAPANESE

鳥が歌を歌っています。

BACK INTO ENGLISH

The bird is singing a song.

INTO JAPANESE

鳥は歌を歌っている。

BACK INTO ENGLISH

Birds are singing songs.

INTO JAPANESE

鳥は歌を歌っている。

BACK INTO ENGLISH

Birds are singing songs.