Mdd
abbr. microgram per square decimeter per day 微克/分米/天（腐蚀速率单位）
🗣️ 情景例句
for a long time,
很久了，
I don't like the way you always keep me waiting.
我不喜欢你常常让我久等。
He is taller than I by ahead.
他比我高一头。