YOU SAID:

There was a sound of dry leaves outside.

INTO JAPANESE

外に乾いた葉の音が聞こえた。

BACK INTO ENGLISH

I heard the sound of dry leaves outside.

INTO JAPANESE

外の葉の乾燥音が聞こえた。

BACK INTO ENGLISH

I heard the dryness of the leaves outside.

INTO JAPANESE

外の葉の乾燥が聞こえた。

BACK INTO ENGLISH

I heard the leaves outside dry.

INTO JAPANESE

外の葉が乾いているのが聞こえた。

BACK INTO ENGLISH

I heard the leaves outside dry.