If it was the other way around, A would not have acted out like B.
If the roles were reversed, A would not have acted immaturely like B.
●If it was the other way around, A would not have acted out like B.
「もし逆（の立場）だったら、AはBみたいに感情をあらわに出さないだろう。」
the other way around➔逆に、反対に
act out➔感情をあらわに出す
●If the roles were reversed, A would not have acted immaturely like B.
「もし逆の立場だったら、AはBのように子供っぽく振舞わなかっただろう。」
role➔役割
reverse➔逆にする、入れ替える
immaturely➔幼稚な、子供っぽい
少しでもお役に立てれば幸いです。
日本 
