Udc
abbr. 国际十进位分类（universal decimal classification）
🗣️ 情景例句
Are you carrying any items that need to be declared?
你没有携带需要申报的东西吗？
I was born in China and brought up in the U.S.A.
我出生在中国，在美国长大。
As a reasonable guess, they might, on an average, be 100 light years away.
据合理推算，外星人离我们平均距离也有100光年之远