题干
—When _________ you have a book sale?
—Sorry, I _________ know.
A：are; don't
B：do: aren't
C：are, aren't
D：do; don't
答案(点此获取答案解析）
D
—When _________ you have a book sale?
—Sorry, I _________ know.
A：are; don't
B：do: aren't
C：are, aren't
D：do; don't
