Back mutation
回复突变
🧩 词语组成解析
back
[bæk]
n. 背，背部;背面，反面;后面，后部;（椅子等的）靠背;
vt. 使后退;支持;加背书于;下赌注于;
vi. 后退;倒退;
adj. 背部的;后面的;以前的;拖欠的;
adv. 以前;向后地;
🗣️ 情景例句
It certainly is. The sun is shining but there's pleasant breeze. It's lovely.
的确不错。阳光明媚，和风宜人。太舒心了。
What platform does the train leave from?
这班车从哪个站台开出呢？
It's a pleasure working with you.
与您合作很愉快。