YOU SAID:

Three little birds sat on my window

INTO JAPANESE

3羽の小鳥が私の窓に座った

BACK INTO ENGLISH

Three birds sat in my window.

INTO JAPANESE

私の窓には三羽の鳥が座っていました。

BACK INTO ENGLISH

There were three birds sitting in my window.

INTO JAPANESE

私の窓には3羽の鳥が座っていた。

BACK INTO ENGLISH

There were three birds sitting in my window.