题干
A. It's a cake.
B. Hello, Li Hong.
C. Thank you.
Li Hong: Hello, Gao Ling.
Gao Ling: ____
Li Hong: What's this?
Gao Ling: ____ Happy birthday to you.
Li Hong: ____
Gao Ling: You're welcome（不用客气）.
答案(点此获取答案解析）
B,A,C
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