学习首先了解各种包装材料的特性，规格以及主要用途。
查看答案
只有充分认识材料的结构，制备，性质与效能之间的相互影响关系，才能将材料的性能发挥到极致，设计出精美的包装
A. 对
B. 错
Q1: What will Isabelle get for her birthday?
Q2: Will she love the birthday present that her parents bought for her?
Q3: How to express uncertainty according to the video clip?
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