Dorsoventrality
背腹性
🗣️ 情景例句
How long does it take you to get through a letter?
你写一封信要花多少时间？
We are thinking of placing an order for your Flying Pigeon Brand bicycles. We would be very grateful if you could make us an offer for 200 ones with details.
我们正打算订购你方的飞鸽牌自行车。如果你们能给我们（购买200台的详细报盘将不胜感激。
and even so, some starting data has to guessed,
既使是这样，有些开始时的资料也不得不依靠推测，