0 not happening very often -- 很少发生的，罕见的
His letters became infrequent, then stopped completely. 他的信来得少了，之后干脆彻底不来了。
In summary, relationships with nieces and nephews for most of those with families at a distance are primarily symbolic, perfunctory and infrequent.
One could not count on this, however, as these visits were infrequent and short.
For example, the public home-help service, if received at all, typically provides only infrequent cleaning of just one room and the kitchen.
Ability to access best practice statement easily even if type of care is infrequent.
That is, the interventions by the supernatural are infrequent and, hence, inconsequential to the processes and regularities of the development of civilization.
One difficulty is that the word is relatively late-emerging and infrequent, indicating a metacognitive level of understanding.
If litigation over the initial terms of hire was infrequent, mariners often complained when masters or merchants changed a ship's destination midvoyage.
This suggests that the zero subject relative may always have been an infrequent option, as remains so, at least in these peripheral dialect areas.
