alternately

in succession one person at a time

rather

alternative as a substitute in lieu in place of in preference on behalf of on second thought preferably rather than

at intervals at times every once in a while every so often fluctuating from time to time irregularly now and then occasionally on occasion once in a while sometimes sporadically vacillating variably

at irregular intervals fluctuating hardly infrequently intermittent irregularly not often on and off scarcely sometimes sporadically vacillating variable very seldom when the mood strikes

at irregular intervals fluctuating inconstantly infrequently intermittently irregularly not often now and then off and on sometimes sporadically uncertainly variable very seldom when the mood strikes

sooner willingly

alternatively as a matter of choice by choice by preference first in lieu of in preference just as soon more readily more willingly much sooner

extremely insignificantly little violently

infrequently occasionally periodically

again betimes cyclically discontinuously sometimes