Polyacetals
聚缩醛(树脂)
🗣️ 情景例句
my grandfather is
我爷爷
I can do.
我会做。
I'm not sure. It was difficult to see. Wei Hua and Sun Meiying were both neck and neck.
我不敢肯定。很难说。魏华和孙美英不分上下。