returning home, she found a note to the door, reading: “Call in later.”
A. On; attaching
B. On; attached
C. At; attaching
D. At; attached
网友回答
A. On; attaching
(答案→)B. On; attached
C. At; attaching
D. At; attached
解析：本题考查介词和非谓语动词。便条note是被粘贴在门上的，所以用过去分词表示被动。On doing sth表示一……就……。