someone’s letter, the letter that…; a … letter
That letter you should have replied to... the one you never answered.
— 甘泉玛侬 (1986)
The letters this poet has received over the past two days are piled as high as a mountain.
— 邮差 (1994)
Now, on behalf of my father, I’m sending you all these letters from sixty years ago.
— 海角七号 (2008)
This is a letter from the school saying that you haven’t been attending school for several months.
— 好家伙 (1990)