美句仿写

1. It was a time when the killer whales，or “killers” as they were then called，helped the whalers catch the baleen whales that were on their annual migration.这是虎鲸帮助捕鲸人在须鲸一年一度的迁徙过程中捕捉须鲸的时候。(P19) [句型] It was/is a time when… [说明] It was/is a time when 曾经一度(那时), when引导定语从句，修饰time。