Mesoectoblast
[医] 中外胚层
🗣️ 情景例句
He had insufficient sleep.
他睡眼不足。
He has a pound of beef.
他有一磅牛肉。
A temporary rudder was made on board from spare planks and it was fitted with great difficulty.
船员用备用的木板在船上赶制了一只应急用的舵，并克服重重困难将舵安装就位，