题干
_________ Day is coming. I'll buy some ________ for Miss Wu。（ ）
A：Teacher's, flower
B：Teachers', flowers
C：Teachers', flower
答案(点此获取答案解析）
B
_________ Day is coming. I'll buy some ________ for Miss Wu。（ ）
A：Teacher's, flower
B：Teachers', flowers
C：Teachers', flower
组溶液，不用试剂也能鉴别开来的是