D-usnic acid
[化] 右旋地衣酸
🧩 词语组成解析
🗣️ 情景例句
I can't answer that one.
我回答不出那个问题。
It's a pain in the neck having to meet them at the airport.
必须到机场去接他们，真讨厌。
The main school holidays are from mid-December till early February when the days are long and warm.
学校主要的假期从12月中旬起至第二年的2月初为止，这段时间白昼很长，气候也暖和。