But every now and then nuclear deterrence becomes a subject of wide public concern .
然而,核威慑却时常成为公众广泛关注的话题。
Every now and then great parties suffer internecine convulsions .
大型政党总会时不时地遭遇两败俱伤的内斗。
Every now and then the freemans invite their neighbours round to their front porch to watch the world go by drink beer and eat connie 's justly renowned dish of minnesota wild rice .