根据对话内容，选择适当的句子补全对话。A.You are right.B. It
题型：补全对话，情景问答
问题：
| 根据对话内容，选择适当的句子补全对话。 | |
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| A: What's this in the picture? B: 1 A: Oh,I see. 2 , families put up Christmas trees in their living rooms, don't they? B: Yes. 3 A: And what's this at the top of the tree? B: 4 A: What's under the tree? B: 5 |
知，B与F成正比，与IL成反比