YOU SAID:
I'll be the leader of the fish chorus.
INTO JAPANESE
私は魚のコーラスのリーダーになるでしょう。
BACK INTO ENGLISH
I will be the leader of the fish chorus.
INTO JAPANESE
私は魚のコーラスのリーダーになります。
BACK INTO ENGLISH
I will be the leader of the fish chorus.
That didn't even make that much sense in English.