题目内容：

this letter is from _his friend______,划线提问 1--------------------- 2-------------------
1___ ______ is this letter
2 ___ is _________

优质解答

单从整个句子来看,问的是信从哪里来,应该选where 但对画线提问的是my friend 从my friend来看,Who is the letter from是正确答案 应该是who ..