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
I haven't decided whether I will go camping or not, but it is certainly possible.
我还没决定是否去露营，但还是有可能去的。
A hero is known in the time of misfortune.
时势造英雄。
Some of them were as big as marbles.
有的钻石像玻璃球那么大。