Challenge-response
挑战-应答
🧩 词语组成解析
challenge
['tʃælɪndʒ]
n. 挑战;盘问;质疑;怀疑;
vt. 质疑;向…挑战;
vi. 提出挑战，要求竞赛（或竞争）;驳斥;
🗣️ 情景例句
on the patio this morning.
要在院子 。
I took out my pen.
我拿出了我的笔。
Hmm! That's a bit expensive. Can I try them on, please?
嗯！就是贵了一点儿。我可以试穿一下吗？