当然だ/当たり前だ => natural; as a matter of course N2
急に => quickly; immediately; hastily; suddenly; abruptly; unexpectedly ~ N4
一応 => more or less; pretty much; roughly; tentatively ~ N2
に応じて => depending on; in accordance with ~ N2
手前 => considering; before; in front of; one’s standpoint N1
のが上手 => to be good at doing something N5
のが下手 => to be bad at doing something N5
に[応「おう」]じて(は)/に[応「おう」]じ(た) => In response/reply to A, In line with A; That fits with A N2
Based, Focused, Depending on