Polyacetals
聚缩醛(树脂)
🗣️ 情景例句
If there's anything you need, please call me.
假如你们需要什么， 请打电话给我。
I used to set my alarm clock for exactly 7 a.m.
我过去常将闹钟调为上午7点整。
Fine.we're saving a lot of money with it.
不错，节省了不少的钱，