将来完成时： e.g. By the end of next term 2000 English words will have been learned. The building will have been built by next year. 现在完成时：e.g. All the tickets have been sold . The book has been translated into many languages.这本书已被译成多种语言。 过去完成时：e.g. Forty schools had been visited by last year. All the tickets had been sold out when I got to the cinema.

will have been+过去分词

has/have + bee n +过去分词

had been+过去分词