When I play the piano, I can imagine what I want to play but it is difficult to express it in sound
When I play the piano, imagining the music is easy but actually playing it is difficult
「ピアノを弾くとき、イメージは出来るけど、そのイメージを音で表現するのは難しい」＝ When I play the piano, I can imagine what I want to play but it is difficult to express it in sound / When I play the piano, imagining the music is easy but actually playing it is difficult
ボキャブラリー・フレーズ
play the piano ＝ ピアノを弾く
I can imagine ＝ 想像できる、イメージできる
what I want to play ＝ 引きたい音楽・事
it is difficult to ＝ ～する事が難しい
actually ＝ 実際に
express ＝ 表現する
イギリス 
