Icrf
国际天球参考架
🗣️ 情景例句
Carl, you're sure you've never played?
Carl，你肯定你从来没玩过吗？
In my opinion, the product must be priced under $ 300.
就我的意见来说，产品价格必须订在300美元以下。
So was born the echo-sounding apparatus, now in general use in ships.
这样就产生了目前各种船舶上普遍应用的回声探测仪。