Polyisobutene
聚异丁烯; 聚异丁烯
🗣️ 情景例句
How much do stamps cost?
邮票多少钱？
Prevention is better than cure.
预防胜于治疗。
Now, this is the chemistry lab. Have you been in this lab before?
好啦，这是化学实验室。你们以前到过这个实验室吗？