じっくり (translations)→ carefully close closely extra fastidiously good long methodically patiently relish smooth thoughtfully
すっかり (translations)→ absolutely all already altogether anew awful certainly completely deep deeply dramatically drastically dreadfully easily every everything exactly extremely fairly finally forever freely full fully genuinely hopelessly indeed late much nicely noticeably perfectly quite rapidly real really ridiculously severly significantly simply so splendidly spoil stone sufficiently superfluous terribly totally unmitigated very well whole
ほんとうに (translations)→ actually adventure boring honestly how just particularly pretty rather sheer yes
まじめに (translations)→ sober studiously
まともに (translations)→ direct directly entirely full-scale hard levelly pat practically properly reasonable right sensibly smack squarely straight unerringly
よく (translations)→ again almost always better common constantly enormously exceedingly frequent frequently further great intimately like lot many mostly occasional often once periodically prolonged respectable sometimes soundly strongly usually vigorous
よくよく (translations)→ jolly more scrupulously
鹿爪らしく (translations)→ formally serious stiff
重い (translations)→ heavy weight
深刻な (translations)→ big disabling grave important significant sorely terrible
真っ向から (translations)→ steadily
真顔で (translations)→ dryly earnestly frankly gravely intently judiciously solemnly
真剣に (translations)→ engage keenly preoccupied urgently
真剣味 (translations)→ importance seriousness
絶対に (translations)→ absolute complete ever never obviously secrecy strictly sure utterly
熱心な (translations)→ alert attentive committed dedicated diligent enthusiasm fain fervent inspired intense passionate practicing sharp wedded willing zealous zestful
熱心に (translations)→ actively alertly assiduously attentively busy eagerly earnest faithfully fervently lively steadfast vigorously