Ddf
[计] 数据库描述文件, 开发论证设施
🗣️ 情景例句
I always mix up these two words.
我老是把这两个词搞混。
One cannot always be a hero, but one can always be a man.
人难一世称雄，但可一生为人。
His engine failed and he landed on the sea for the second time.
这次他又遭厄运，因引擎故障第二次降落在海面上。