问题补充：
Between the two parts of the concert is an interval, the audience can buy ice-cream.
A. when
B. where
C. that
D. which
答案：
(答案→)A. when
B. where
C. that
D. which
解析：本题考查定语从句。the audience 为主语，can buy为谓语，ice-cream为宾语，所以从句完整，不能用关系代词。所以要用关系副词，先行词是interval,表示“间隔”,是时间，所以用when.
