must have pp와 should have pp의 의미를 구분해야 한다. 전자는 '..했었음에 틀림없다'이고 후자는 '...했었어야 했는데(못 했다)'라는 의미이다. . ① At a famous restaurant I was once served food so old that it had gone bad. ② I could smell the rotten meat before the waiter put it on my table. ③ Foolishly, I screamed insults at the waiter who brought those dishes. ④ Directly after that, however, I realized that it wasn't the waiter's fault. ⑤ I ..