unannounced

adj

• ① 未经声明[公布、发表]的

• ② 未经通报的,未先通知的,突然出现的
  • He arrived unannounced.他突然来到。
  • He entered the house unannounced.他未经通报就进入那栋房子。
  • His visit to France was unannounced.他的访问法国未先通告。