一心 いっしん
isshinni

Adverb

1. wholeheartedly; single-mindedly; fervently; intently

Related to 一心
そのピアニストの演奏 えんそう ちゅう、彼 かれらは一心 いっしん みみ かたむけた。
sono pianisutono ensōchū karerawa isshinni mimio katamuketa.
They were all ears while the pianist was playing.