1、经常的英语：often，英 [ˈɒfn] 美 [ˈɔːfn]。 2、人们经常谈到两者的相似之处。The similarities between the two have often been remarked on。 3、这种疾病经常潜伏多年而不被察觉。The disease often goes/ remains undetected for many years。 4、从前的夏天...