Translation of "Responsive" in Japanese

He was very kind and responsive.

彼は優しくて愛想のいいだった。

It is not the strongest of the species that survives, not the most intelligent, but the one most responsive to change.

最も力の強い種や、最も知能の高い種が生き残るのではなく、変化に最も良く適応できる種が生き残るのです。

It is not the strongest of the species that survive, nor the most intelligent, but the one most responsive to change.

最も強い種でも最も賢い種でもなく、生き残るのは最も変化に対応できる種だ。