围绕本课标题 Is that all? 就这些吗？（在文具店 · 购物对话）主题，AI 老师会出 若干个简单问题，
每个问题听完后，用 完整句子口头作答。
⚠️ 尽量说完整句子，不要只说一个词；优先用本课句型与词语：I want some envelopes / the large size or the small size / Do you have any writing paper / a bottle of glue / Do you want a pad / Is that all / my change