Backpitch
反螺旋; 背节距
🗣️ 情景例句
Yes, it's so easy.
没错， 它真简便。
The data confirm that this product is safe and effective.
数据证实此种产品安全有效。
Not very popular. We play American football in the USA.
不很受欢迎。在美国我们踢美式足球。