1 不时
occasional ever and again at short intervals for time to time upon occasion ever and anon now and then on and off on occasion off and on now and again
2 经常地
away ever constantly aye ever and anon
3 不时地
ever and again at short intervals for time to time upon occasion ever and anon on and off on occasion off and on
4 经常
usual overhead inevitable wont unending away ever frequently constantly aye evermore make it a rule to V ever and anon for evermore make a point of