What surprised me most是主语从句，that Tom even didn’t know whether there was any difference between the two words that he had learned when I met and asked him the other day 是表语从句，whether there was any difference between the two words that he had learned when I met and asked him the other day 是宾语从句，that he had learned when I met and asked him the other day 是定语从句，??when I met and asked him the other day是时间状语从句。全句译文：最使我感到惊奇的（事情）是汤姆甚至不知道几天前我遇见和问他时他学过的那两个词之间是否有不同之处。