添削お願いします。
I have conviction that you were surprised when you have listened this song playing by me.
why are you surprise? I will give you a word. listen this! then you will understand it.
自分は確信している。あなたが私の演奏を聴いたときに驚くことを。
何故あなたが驚くかって。私からあなたへ一言。聞けば分かるさ。