1970年佛瑞德退休了，打那以后他们一直居住在塞勒姆市。
He retired in 1970, and they have lived in Salem since then.
塞佛和他的妻子西格丽德听力都不好，塞佛还戴了两个助听器，使他不必依靠唇读和手语。
Both Cerf and his wife, Sigrid, have hearing impairments. Cerf wears two hearing AIDS that enable him to not rely on lip reading or sign language.
长期以来，人们一直用临界流速或临界佛汝德数的准则来确定冰塞的演变。
The critical velocity, or critical Froude number criterion has long been accepted as a means of determining frazil jam profiles.
应用推荐