Backcross
vt.vi. 使回交, (使)逆代杂交
✅ 同义词
🗣️ 情景例句
is tomorrow morning at ten o'clock.
明天早上十点。
How much is it by air mail?
航空信要多少钱？
To such motives, yet another must be added.
除了以上动机外，还应再加上一个。