Jacobian
[计] 雅可比
🗣️ 情景例句
How long does your vacation last?
你的假期有多长？
If there were no clouds, we should not enjoy the sun.
吃得苦中苦，方知甜中甜。
'We mustn't buy things we don't need,' I remarked suddenly.
“我们不应该买我们不需要的东西，”我突然发表意见说，