いつまでも (translations)→ always continually continue endlessly eternal forever indelibly interminably long remain still
しきりに (translations)→ bitterly busily conjecture copiously desperately eagerly earnestly fluently frequently furiously hard imperiously insistently intently keep much often rapid steadfastly terribly urge urgent urgently variously
たえず (translations)→ ceaselessly constant endless invariably permanently perpetual
ひっきりなしに (translations)→ constantly continuous incessant steadily steady unceasing
