Polyanhydrides
[化] 聚酐類
??? 情景例句
No problem. we all make mistakes.
沒問題。 人人都有犯錯(cuò)的時(shí)候。
Americans are hight mobile, and therefore may find it difficult to became deeply involued with other.
美國人的流動(dòng)性，大，因此你會(huì)發(fā)現(xiàn)和他人深交很難。
of a change of atmosphere, of a diversion of effort, is essential.
改變一下氣氛，轉(zhuǎn)移一下注意力，這是不可缺少的。