| occasionally(expression, adverb, time, moment, period) |
| sometimes(expression, adverb, time, moment, period) |
| now and then(expression, idiom, adverb, time, moment) |
| at times(expression, adverb, time, moment, period) |
| every so often(expression, idiom, adverb, time, moment) |
| off and on(expression, idiom, adverb, time, moment) |
| infrequently(expression, adverb, time, moment, period) |
| sporadically(expression, adverb, time, rare, frequency) |
| now and again(expression, adverb, time, moment, rare) |
| betweentimes(expression, adverb, time, moment, period) |
| every once in a while(expression, idiom, adverb, time, moment) |
| once in a while(expression, adverb, time, moment, rare) |
| once again |
| at intervals(expression, adverb, time, rare, vacillating) |
| ever and again(expression, adverb, time, moment, rare) |
| from time to time(expression, adverb, time, moment, rare) |
| in some cases |
| irregularly(adverb, occasionally) |
| on and off(expression, adverb, time, moment, rare) |
| once(expression, adverb, time, moment, period) |