抗氧剂：有的聚合物，如聚丙烯，如果其中不加适当的稳定剂，就 不能在户外使用，这是因为它分子中的叔碳原子上存在着易消除的氢原 子。

Antioxidants: Polymers such as polypropylene (PP) are not usable outdoors without appropriate stabilizers, because of the presence of readily removable hydrogen atoms on the tertiary carbon atoms.

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李老三心里想：等到过年春子回来，就和刘四叔商量一下，给孩子们定了亲，这样来往也方便些。

Lilaosan thought: wait until Chunzi came back to New Year, they and uncle Liu-si discuss with Tetra, give the kids set the affinity, so travel is also convenient.

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