recrudesce

如果不加以治疗，这种疾病可能会在几年后再次爆发。

If left untreated, the disease may ___recrudesce years later.

随着经济衰退的加剧，社会动荡再次出现。

Social unrest began to ___recrudesce as the economic recession deepened.

尽管停火，暴力冲突仍可能随时再次爆发。

Despite the ceasefire, violence could ___recrudesce at any time.